ProfessionalWiki / Bootstrap

SCSS/vendor/scssphp/scssphp/src/Formatter/Expanded.php

Indentation +38 added lines, -38 removed lines

@@ -22,48 +22,48 @@
  */
 class Expanded extends Formatter
 {
-    /**
-     * {@inheritdoc}
-     */
-    public function __construct()
-    {
-        $this->indentLevel = 0;
-        $this->indentChar = '  ';
-        $this->break = "\n";
-        $this->open = ' {';
-        $this->close = '}';
-        $this->tagSeparator = ', ';
-        $this->assignSeparator = ': ';
-        $this->keepSemicolons = true;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function __construct()
+	{
+		$this->indentLevel = 0;
+		$this->indentChar = '  ';
+		$this->break = "\n";
+		$this->open = ' {';
+		$this->close = '}';
+		$this->tagSeparator = ', ';
+		$this->assignSeparator = ': ';
+		$this->keepSemicolons = true;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected function indentStr()
-    {
-        return str_repeat($this->indentChar, $this->indentLevel);
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function indentStr()
+	{
+		return str_repeat($this->indentChar, $this->indentLevel);
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    protected function blockLines(OutputBlock $block)
-    {
-        $inner = $this->indentStr();
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function blockLines(OutputBlock $block)
+	{
+		$inner = $this->indentStr();
 
-        $glue = $this->break . $inner;
+		$glue = $this->break . $inner;
 
-        foreach ($block->lines as $index => $line) {
-            if (substr($line, 0, 2) === '/*') {
-                $block->lines[$index] = preg_replace('/\r\n?|\n|\f/', $this->break, $line);
-            }
-        }
+		foreach ($block->lines as $index => $line) {
+			if (substr($line, 0, 2) === '/*') {
+				$block->lines[$index] = preg_replace('/\r\n?|\n|\f/', $this->break, $line);
+			}
+		}
 
-        $this->write($inner . implode($glue, $block->lines));
+		$this->write($inner . implode($glue, $block->lines));
 
-        if (empty($block->selectors) || ! empty($block->children)) {
-            $this->write($this->break);
-        }
-    }
+		if (empty($block->selectors) || ! empty($block->children)) {
+			$this->write($this->break);
+		}
+	}
 }

Spacing +1 added lines, -1 removed lines

@@ -62,7 +62,7 @@
 
         $this->write($inner . implode($glue, $block->lines));
 
-        if (empty($block->selectors) || ! empty($block->children)) {
+        if (empty($block->selectors) || !empty($block->children)) {
             $this->write($this->break);
         }
     }

SCSS/vendor/scssphp/scssphp/src/Formatter/OutputBlock.php

Indentation +36 added lines, -36 removed lines

@@ -19,48 +19,48 @@
  */
 class OutputBlock
 {
-    /**
-     * @var string
-     */
-    public $type;
+	/**
+	 * @var string
+	 */
+	public $type;
 
-    /**
-     * @var integer
-     */
-    public $depth;
+	/**
+	 * @var integer
+	 */
+	public $depth;
 
-    /**
-     * @var array
-     */
-    public $selectors;
+	/**
+	 * @var array
+	 */
+	public $selectors;
 
-    /**
-     * @var array
-     */
-    public $lines;
+	/**
+	 * @var array
+	 */
+	public $lines;
 
-    /**
-     * @var array
-     */
-    public $children;
+	/**
+	 * @var array
+	 */
+	public $children;
 
-    /**
-     * @var \ScssPhp\ScssPhp\Formatter\OutputBlock
-     */
-    public $parent;
+	/**
+	 * @var \ScssPhp\ScssPhp\Formatter\OutputBlock
+	 */
+	public $parent;
 
-    /**
-     * @var string
-     */
-    public $sourceName;
+	/**
+	 * @var string
+	 */
+	public $sourceName;
 
-    /**
-     * @var integer
-     */
-    public $sourceLine;
+	/**
+	 * @var integer
+	 */
+	public $sourceLine;
 
-    /**
-     * @var integer
-     */
-    public $sourceColumn;
+	/**
+	 * @var integer
+	 */
+	public $sourceColumn;
 }

SCSS/vendor/scssphp/scssphp/src/Formatter/Nested.php

Indentation +205 added lines, -205 removed lines

@@ -23,209 +23,209 @@
  */
 class Nested extends Formatter
 {
-    /**
-     * @var integer
-     */
-    private $depth;
-
-    /**
-     * {@inheritdoc}
-     */
-    public function __construct()
-    {
-        $this->indentLevel = 0;
-        $this->indentChar = '  ';
-        $this->break = "\n";
-        $this->open = ' {';
-        $this->close = ' }';
-        $this->tagSeparator = ', ';
-        $this->assignSeparator = ': ';
-        $this->keepSemicolons = true;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function indentStr()
-    {
-        $n = $this->depth - 1;
-
-        return str_repeat($this->indentChar, max($this->indentLevel + $n, 0));
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function blockLines(OutputBlock $block)
-    {
-        $inner = $this->indentStr();
-        $glue  = $this->break . $inner;
-
-        foreach ($block->lines as $index => $line) {
-            if (substr($line, 0, 2) === '/*') {
-                $block->lines[$index] = preg_replace('/\r\n?|\n|\f/', $this->break, $line);
-            }
-        }
-
-        $this->write($inner . implode($glue, $block->lines));
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function block(OutputBlock $block)
-    {
-        static $depths;
-        static $downLevel;
-        static $closeBlock;
-        static $previousEmpty;
-        static $previousHasSelector;
-
-        if ($block->type === 'root') {
-            $depths = [ 0 ];
-            $downLevel = '';
-            $closeBlock = '';
-            $this->depth = 0;
-            $previousEmpty = false;
-            $previousHasSelector = false;
-        }
-
-        $isMediaOrDirective = \in_array($block->type, [Type::T_DIRECTIVE, Type::T_MEDIA]);
-        $isSupport = ($block->type === Type::T_DIRECTIVE
-            && $block->selectors && strpos(implode('', $block->selectors), '@supports') !== false);
-
-        while ($block->depth < end($depths) || ($block->depth == 1 && end($depths) == 1)) {
-            array_pop($depths);
-            $this->depth--;
-
-            if (
-                ! $this->depth && ($block->depth <= 1 || (! $this->indentLevel && $block->type === Type::T_COMMENT)) &&
-                (($block->selectors && ! $isMediaOrDirective) || $previousHasSelector)
-            ) {
-                $downLevel = $this->break;
-            }
-
-            if (empty($block->lines) && empty($block->children)) {
-                $previousEmpty = true;
-            }
-        }
-
-        if (empty($block->lines) && empty($block->children)) {
-            return;
-        }
-
-        $this->currentBlock = $block;
-
-        if (! empty($block->lines) || (! empty($block->children) && ($this->depth < 1 || $isSupport))) {
-            if ($block->depth > end($depths)) {
-                if (! $previousEmpty || $this->depth < 1) {
-                    $this->depth++;
-
-                    $depths[] = $block->depth;
-                } else {
-                    // keep the current depth unchanged but take the block depth as a new reference for following blocks
-                    array_pop($depths);
-
-                    $depths[] = $block->depth;
-                }
-            }
-        }
-
-        $previousEmpty = ($block->type === Type::T_COMMENT);
-        $previousHasSelector = false;
-
-        if (! empty($block->selectors)) {
-            if ($closeBlock) {
-                $this->write($closeBlock);
-                $closeBlock = '';
-            }
-
-            if ($downLevel) {
-                $this->write($downLevel);
-                $downLevel = '';
-            }
-
-            $this->blockSelectors($block);
-
-            $this->indentLevel++;
-        }
-
-        if (! empty($block->lines)) {
-            if ($closeBlock) {
-                $this->write($closeBlock);
-                $closeBlock = '';
-            }
-
-            if ($downLevel) {
-                $this->write($downLevel);
-                $downLevel = '';
-            }
-
-            $this->blockLines($block);
-
-            $closeBlock = $this->break;
-        }
-
-        if (! empty($block->children)) {
-            if ($this->depth > 0 && ($isMediaOrDirective || ! $this->hasFlatChild($block))) {
-                array_pop($depths);
-
-                $this->depth--;
-                $this->blockChildren($block);
-                $this->depth++;
-
-                $depths[] = $block->depth;
-            } else {
-                $this->blockChildren($block);
-            }
-        }
-
-        // reclear to not be spoiled by children if T_DIRECTIVE
-        if ($block->type === Type::T_DIRECTIVE) {
-            $previousHasSelector = false;
-        }
-
-        if (! empty($block->selectors)) {
-            $this->indentLevel--;
-
-            if (! $this->keepSemicolons) {
-                $this->strippedSemicolon = '';
-            }
-
-            $this->write($this->close);
-
-            $closeBlock = $this->break;
-
-            if ($this->depth > 1 && ! empty($block->children)) {
-                array_pop($depths);
-                $this->depth--;
-            }
-
-            if (! $isMediaOrDirective) {
-                $previousHasSelector = true;
-            }
-        }
-
-        if ($block->type === 'root') {
-            $this->write($this->break);
-        }
-    }
-
-    /**
-     * Block has flat child
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
-     *
-     * @return boolean
-     */
-    private function hasFlatChild($block)
-    {
-        foreach ($block->children as $child) {
-            if (empty($child->selectors)) {
-                return true;
-            }
-        }
-
-        return false;
-    }
+	/**
+	 * @var integer
+	 */
+	private $depth;
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function __construct()
+	{
+		$this->indentLevel = 0;
+		$this->indentChar = '  ';
+		$this->break = "\n";
+		$this->open = ' {';
+		$this->close = ' }';
+		$this->tagSeparator = ', ';
+		$this->assignSeparator = ': ';
+		$this->keepSemicolons = true;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function indentStr()
+	{
+		$n = $this->depth - 1;
+
+		return str_repeat($this->indentChar, max($this->indentLevel + $n, 0));
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function blockLines(OutputBlock $block)
+	{
+		$inner = $this->indentStr();
+		$glue  = $this->break . $inner;
+
+		foreach ($block->lines as $index => $line) {
+			if (substr($line, 0, 2) === '/*') {
+				$block->lines[$index] = preg_replace('/\r\n?|\n|\f/', $this->break, $line);
+			}
+		}
+
+		$this->write($inner . implode($glue, $block->lines));
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function block(OutputBlock $block)
+	{
+		static $depths;
+		static $downLevel;
+		static $closeBlock;
+		static $previousEmpty;
+		static $previousHasSelector;
+
+		if ($block->type === 'root') {
+			$depths = [ 0 ];
+			$downLevel = '';
+			$closeBlock = '';
+			$this->depth = 0;
+			$previousEmpty = false;
+			$previousHasSelector = false;
+		}
+
+		$isMediaOrDirective = \in_array($block->type, [Type::T_DIRECTIVE, Type::T_MEDIA]);
+		$isSupport = ($block->type === Type::T_DIRECTIVE
+			&& $block->selectors && strpos(implode('', $block->selectors), '@supports') !== false);
+
+		while ($block->depth < end($depths) || ($block->depth == 1 && end($depths) == 1)) {
+			array_pop($depths);
+			$this->depth--;
+
+			if (
+				! $this->depth && ($block->depth <= 1 || (! $this->indentLevel && $block->type === Type::T_COMMENT)) &&
+				(($block->selectors && ! $isMediaOrDirective) || $previousHasSelector)
+			) {
+				$downLevel = $this->break;
+			}
+
+			if (empty($block->lines) && empty($block->children)) {
+				$previousEmpty = true;
+			}
+		}
+
+		if (empty($block->lines) && empty($block->children)) {
+			return;
+		}
+
+		$this->currentBlock = $block;
+
+		if (! empty($block->lines) || (! empty($block->children) && ($this->depth < 1 || $isSupport))) {
+			if ($block->depth > end($depths)) {
+				if (! $previousEmpty || $this->depth < 1) {
+					$this->depth++;
+
+					$depths[] = $block->depth;
+				} else {
+					// keep the current depth unchanged but take the block depth as a new reference for following blocks
+					array_pop($depths);
+
+					$depths[] = $block->depth;
+				}
+			}
+		}
+
+		$previousEmpty = ($block->type === Type::T_COMMENT);
+		$previousHasSelector = false;
+
+		if (! empty($block->selectors)) {
+			if ($closeBlock) {
+				$this->write($closeBlock);
+				$closeBlock = '';
+			}
+
+			if ($downLevel) {
+				$this->write($downLevel);
+				$downLevel = '';
+			}
+
+			$this->blockSelectors($block);
+
+			$this->indentLevel++;
+		}
+
+		if (! empty($block->lines)) {
+			if ($closeBlock) {
+				$this->write($closeBlock);
+				$closeBlock = '';
+			}
+
+			if ($downLevel) {
+				$this->write($downLevel);
+				$downLevel = '';
+			}
+
+			$this->blockLines($block);
+
+			$closeBlock = $this->break;
+		}
+
+		if (! empty($block->children)) {
+			if ($this->depth > 0 && ($isMediaOrDirective || ! $this->hasFlatChild($block))) {
+				array_pop($depths);
+
+				$this->depth--;
+				$this->blockChildren($block);
+				$this->depth++;
+
+				$depths[] = $block->depth;
+			} else {
+				$this->blockChildren($block);
+			}
+		}
+
+		// reclear to not be spoiled by children if T_DIRECTIVE
+		if ($block->type === Type::T_DIRECTIVE) {
+			$previousHasSelector = false;
+		}
+
+		if (! empty($block->selectors)) {
+			$this->indentLevel--;
+
+			if (! $this->keepSemicolons) {
+				$this->strippedSemicolon = '';
+			}
+
+			$this->write($this->close);
+
+			$closeBlock = $this->break;
+
+			if ($this->depth > 1 && ! empty($block->children)) {
+				array_pop($depths);
+				$this->depth--;
+			}
+
+			if (! $isMediaOrDirective) {
+				$previousHasSelector = true;
+			}
+		}
+
+		if ($block->type === 'root') {
+			$this->write($this->break);
+		}
+	}
+
+	/**
+	 * Block has flat child
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
+	 *
+	 * @return boolean
+	 */
+	private function hasFlatChild($block)
+	{
+		foreach ($block->children as $child) {
+			if (empty($child->selectors)) {
+				return true;
+			}
+		}
+
+		return false;
+	}
 }

Spacing +13 added lines, -13 removed lines

@@ -82,7 +82,7 @@ 
         static $previousHasSelector;
 
         if ($block->type === 'root') {
-            $depths = [ 0 ];
+            $depths = [0];
             $downLevel = '';
             $closeBlock = '';
             $this->depth = 0;
@@ -99,8 +99,8 @@ 
             $this->depth--;
 
             if (
-                ! $this->depth && ($block->depth <= 1 || (! $this->indentLevel && $block->type === Type::T_COMMENT)) &&
-                (($block->selectors && ! $isMediaOrDirective) || $previousHasSelector)
+                !$this->depth && ($block->depth <= 1 || (!$this->indentLevel && $block->type === Type::T_COMMENT)) &&
+                (($block->selectors && !$isMediaOrDirective) || $previousHasSelector)
             ) {
                 $downLevel = $this->break;
             }
@@ -116,9 +116,9 @@ 
 
         $this->currentBlock = $block;
 
-        if (! empty($block->lines) || (! empty($block->children) && ($this->depth < 1 || $isSupport))) {
+        if (!empty($block->lines) || (!empty($block->children) && ($this->depth < 1 || $isSupport))) {
             if ($block->depth > end($depths)) {
-                if (! $previousEmpty || $this->depth < 1) {
+                if (!$previousEmpty || $this->depth < 1) {
                     $this->depth++;
 
                     $depths[] = $block->depth;
@@ -134,7 +134,7 @@ 
         $previousEmpty = ($block->type === Type::T_COMMENT);
         $previousHasSelector = false;
 
-        if (! empty($block->selectors)) {
+        if (!empty($block->selectors)) {
             if ($closeBlock) {
                 $this->write($closeBlock);
                 $closeBlock = '';
@@ -150,7 +150,7 @@ 
             $this->indentLevel++;
         }
 
-        if (! empty($block->lines)) {
+        if (!empty($block->lines)) {
             if ($closeBlock) {
                 $this->write($closeBlock);
                 $closeBlock = '';
@@ -166,8 +166,8 @@ 
             $closeBlock = $this->break;
         }
 
-        if (! empty($block->children)) {
-            if ($this->depth > 0 && ($isMediaOrDirective || ! $this->hasFlatChild($block))) {
+        if (!empty($block->children)) {
+            if ($this->depth > 0 && ($isMediaOrDirective || !$this->hasFlatChild($block))) {
                 array_pop($depths);
 
                 $this->depth--;
@@ -185,10 +185,10 @@ 
             $previousHasSelector = false;
         }
 
-        if (! empty($block->selectors)) {
+        if (!empty($block->selectors)) {
             $this->indentLevel--;
 
-            if (! $this->keepSemicolons) {
+            if (!$this->keepSemicolons) {
                 $this->strippedSemicolon = '';
             }
 
@@ -196,12 +196,12 @@ 
 
             $closeBlock = $this->break;
 
-            if ($this->depth > 1 && ! empty($block->children)) {
+            if ($this->depth > 1 && !empty($block->children)) {
                 array_pop($depths);
                 $this->depth--;
             }
 
-            if (! $isMediaOrDirective) {
+            if (!$isMediaOrDirective) {
                 $previousHasSelector = true;
             }
         }

SCSS/vendor/scssphp/scssphp/src/Formatter/Crunched.php

Indentation +48 added lines, -48 removed lines

@@ -22,59 +22,59 @@
  */
 class Crunched extends Formatter
 {
-    /**
-     * {@inheritdoc}
-     */
-    public function __construct()
-    {
-        $this->indentLevel = 0;
-        $this->indentChar = '  ';
-        $this->break = '';
-        $this->open = '{';
-        $this->close = '}';
-        $this->tagSeparator = ',';
-        $this->assignSeparator = ':';
-        $this->keepSemicolons = false;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function __construct()
+	{
+		$this->indentLevel = 0;
+		$this->indentChar = '  ';
+		$this->break = '';
+		$this->open = '{';
+		$this->close = '}';
+		$this->tagSeparator = ',';
+		$this->assignSeparator = ':';
+		$this->keepSemicolons = false;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    public function blockLines(OutputBlock $block)
-    {
-        $inner = $this->indentStr();
+	/**
+	 * {@inheritdoc}
+	 */
+	public function blockLines(OutputBlock $block)
+	{
+		$inner = $this->indentStr();
 
-        $glue = $this->break . $inner;
+		$glue = $this->break . $inner;
 
-        foreach ($block->lines as $index => $line) {
-            if (substr($line, 0, 2) === '/*') {
-                unset($block->lines[$index]);
-            }
-        }
+		foreach ($block->lines as $index => $line) {
+			if (substr($line, 0, 2) === '/*') {
+				unset($block->lines[$index]);
+			}
+		}
 
-        $this->write($inner . implode($glue, $block->lines));
+		$this->write($inner . implode($glue, $block->lines));
 
-        if (! empty($block->children)) {
-            $this->write($this->break);
-        }
-    }
+		if (! empty($block->children)) {
+			$this->write($this->break);
+		}
+	}
 
-    /**
-     * Output block selectors
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
-     */
-    protected function blockSelectors(OutputBlock $block)
-    {
-        $inner = $this->indentStr();
+	/**
+	 * Output block selectors
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
+	 */
+	protected function blockSelectors(OutputBlock $block)
+	{
+		$inner = $this->indentStr();
 
-        $this->write(
-            $inner
-            . implode(
-                $this->tagSeparator,
-                str_replace([' > ', ' + ', ' ~ '], ['>', '+', '~'], $block->selectors)
-            )
-            . $this->open . $this->break
-        );
-    }
+		$this->write(
+			$inner
+			. implode(
+				$this->tagSeparator,
+				str_replace([' > ', ' + ', ' ~ '], ['>', '+', '~'], $block->selectors)
+			)
+			. $this->open . $this->break
+		);
+	}
 }

Spacing +1 added lines, -1 removed lines

@@ -54,7 +54,7 @@
 
         $this->write($inner . implode($glue, $block->lines));
 
-        if (! empty($block->children)) {
+        if (!empty($block->children)) {
             $this->write($this->break);
         }
     }

SCSS/vendor/scssphp/scssphp/src/Formatter/Debug.php

Indentation +97 added lines, -97 removed lines

@@ -22,101 +22,101 @@
  */
 class Debug extends Formatter
 {
-    /**
-     * {@inheritdoc}
-     */
-    public function __construct()
-    {
-        $this->indentLevel = 0;
-        $this->indentChar = '';
-        $this->break = "\n";
-        $this->open = ' {';
-        $this->close = ' }';
-        $this->tagSeparator = ', ';
-        $this->assignSeparator = ': ';
-        $this->keepSemicolons = true;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function indentStr()
-    {
-        return str_repeat('  ', $this->indentLevel);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function blockLines(OutputBlock $block)
-    {
-        $indent = $this->indentStr();
-
-        if (empty($block->lines)) {
-            $this->write("{$indent}block->lines: []\n");
-
-            return;
-        }
-
-        foreach ($block->lines as $index => $line) {
-            $this->write("{$indent}block->lines[{$index}]: $line\n");
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function blockSelectors(OutputBlock $block)
-    {
-        $indent = $this->indentStr();
-
-        if (empty($block->selectors)) {
-            $this->write("{$indent}block->selectors: []\n");
-
-            return;
-        }
-
-        foreach ($block->selectors as $index => $selector) {
-            $this->write("{$indent}block->selectors[{$index}]: $selector\n");
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function blockChildren(OutputBlock $block)
-    {
-        $indent = $this->indentStr();
-
-        if (empty($block->children)) {
-            $this->write("{$indent}block->children: []\n");
-
-            return;
-        }
-
-        $this->indentLevel++;
-
-        foreach ($block->children as $i => $child) {
-            $this->block($child);
-        }
-
-        $this->indentLevel--;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function block(OutputBlock $block)
-    {
-        $indent = $this->indentStr();
-
-        $this->write("{$indent}block->type: {$block->type}\n" .
-             "{$indent}block->depth: {$block->depth}\n");
-
-        $this->currentBlock = $block;
-
-        $this->blockSelectors($block);
-        $this->blockLines($block);
-        $this->blockChildren($block);
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function __construct()
+	{
+		$this->indentLevel = 0;
+		$this->indentChar = '';
+		$this->break = "\n";
+		$this->open = ' {';
+		$this->close = ' }';
+		$this->tagSeparator = ', ';
+		$this->assignSeparator = ': ';
+		$this->keepSemicolons = true;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function indentStr()
+	{
+		return str_repeat('  ', $this->indentLevel);
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function blockLines(OutputBlock $block)
+	{
+		$indent = $this->indentStr();
+
+		if (empty($block->lines)) {
+			$this->write("{$indent}block->lines: []\n");
+
+			return;
+		}
+
+		foreach ($block->lines as $index => $line) {
+			$this->write("{$indent}block->lines[{$index}]: $line\n");
+		}
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function blockSelectors(OutputBlock $block)
+	{
+		$indent = $this->indentStr();
+
+		if (empty($block->selectors)) {
+			$this->write("{$indent}block->selectors: []\n");
+
+			return;
+		}
+
+		foreach ($block->selectors as $index => $selector) {
+			$this->write("{$indent}block->selectors[{$index}]: $selector\n");
+		}
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function blockChildren(OutputBlock $block)
+	{
+		$indent = $this->indentStr();
+
+		if (empty($block->children)) {
+			$this->write("{$indent}block->children: []\n");
+
+			return;
+		}
+
+		$this->indentLevel++;
+
+		foreach ($block->children as $i => $child) {
+			$this->block($child);
+		}
+
+		$this->indentLevel--;
+	}
+
+	/**
+	 * {@inheritdoc}
+	 */
+	protected function block(OutputBlock $block)
+	{
+		$indent = $this->indentStr();
+
+		$this->write("{$indent}block->type: {$block->type}\n" .
+			 "{$indent}block->depth: {$block->depth}\n");
+
+		$this->currentBlock = $block;
+
+		$this->blockSelectors($block);
+		$this->blockLines($block);
+		$this->blockChildren($block);
+	}
 }

SCSS/vendor/scssphp/scssphp/src/Formatter/Compact.php

Indentation +21 added lines, -21 removed lines

@@ -21,26 +21,26 @@
  */
 class Compact extends Formatter
 {
-    /**
-     * {@inheritdoc}
-     */
-    public function __construct()
-    {
-        $this->indentLevel = 0;
-        $this->indentChar = '';
-        $this->break = '';
-        $this->open = ' {';
-        $this->close = "}\n\n";
-        $this->tagSeparator = ',';
-        $this->assignSeparator = ':';
-        $this->keepSemicolons = true;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function __construct()
+	{
+		$this->indentLevel = 0;
+		$this->indentChar = '';
+		$this->break = '';
+		$this->open = ' {';
+		$this->close = "}\n\n";
+		$this->tagSeparator = ',';
+		$this->assignSeparator = ':';
+		$this->keepSemicolons = true;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    public function indentStr()
-    {
-        return ' ';
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function indentStr()
+	{
+		return ' ';
+	}
 }

SCSS/vendor/scssphp/scssphp/src/Formatter/Compressed.php

Indentation +50 added lines, -50 removed lines

@@ -22,61 +22,61 @@
  */
 class Compressed extends Formatter
 {
-    /**
-     * {@inheritdoc}
-     */
-    public function __construct()
-    {
-        $this->indentLevel = 0;
-        $this->indentChar = '  ';
-        $this->break = '';
-        $this->open = '{';
-        $this->close = '}';
-        $this->tagSeparator = ',';
-        $this->assignSeparator = ':';
-        $this->keepSemicolons = false;
-    }
+	/**
+	 * {@inheritdoc}
+	 */
+	public function __construct()
+	{
+		$this->indentLevel = 0;
+		$this->indentChar = '  ';
+		$this->break = '';
+		$this->open = '{';
+		$this->close = '}';
+		$this->tagSeparator = ',';
+		$this->assignSeparator = ':';
+		$this->keepSemicolons = false;
+	}
 
-    /**
-     * {@inheritdoc}
-     */
-    public function blockLines(OutputBlock $block)
-    {
-        $inner = $this->indentStr();
+	/**
+	 * {@inheritdoc}
+	 */
+	public function blockLines(OutputBlock $block)
+	{
+		$inner = $this->indentStr();
 
-        $glue = $this->break . $inner;
+		$glue = $this->break . $inner;
 
-        foreach ($block->lines as $index => $line) {
-            if (substr($line, 0, 2) === '/*' && substr($line, 2, 1) !== '!') {
-                unset($block->lines[$index]);
-            } elseif (substr($line, 0, 3) === '/*!') {
-                $block->lines[$index] = '/*' . substr($line, 3);
-            }
-        }
+		foreach ($block->lines as $index => $line) {
+			if (substr($line, 0, 2) === '/*' && substr($line, 2, 1) !== '!') {
+				unset($block->lines[$index]);
+			} elseif (substr($line, 0, 3) === '/*!') {
+				$block->lines[$index] = '/*' . substr($line, 3);
+			}
+		}
 
-        $this->write($inner . implode($glue, $block->lines));
+		$this->write($inner . implode($glue, $block->lines));
 
-        if (! empty($block->children)) {
-            $this->write($this->break);
-        }
-    }
+		if (! empty($block->children)) {
+			$this->write($this->break);
+		}
+	}
 
-    /**
-     * Output block selectors
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
-     */
-    protected function blockSelectors(OutputBlock $block)
-    {
-        $inner = $this->indentStr();
+	/**
+	 * Output block selectors
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
+	 */
+	protected function blockSelectors(OutputBlock $block)
+	{
+		$inner = $this->indentStr();
 
-        $this->write(
-            $inner
-            . implode(
-                $this->tagSeparator,
-                str_replace([' > ', ' + ', ' ~ '], ['>', '+', '~'], $block->selectors)
-            )
-            . $this->open . $this->break
-        );
-    }
+		$this->write(
+			$inner
+			. implode(
+				$this->tagSeparator,
+				str_replace([' > ', ' + ', ' ~ '], ['>', '+', '~'], $block->selectors)
+			)
+			. $this->open . $this->break
+		);
+	}
 }

Spacing +1 added lines, -1 removed lines

@@ -54,7 +54,7 @@
 
         $this->write($inner . implode($glue, $block->lines));
 
-        if (! empty($block->children)) {
+        if (!empty($block->children)) {
             $this->write($this->break);
         }
     }

SCSS/vendor/scssphp/scssphp/src/Compiler.php

Indentation +8147 added lines, -8148 removed lines

@@ -59,8211 +59,8210 @@
  */
 class Compiler
 {
-    const LINE_COMMENTS = 1;
-    const DEBUG_INFO    = 2;
-
-    const WITH_RULE     = 1;
-    const WITH_MEDIA    = 2;
-    const WITH_SUPPORTS = 4;
-    const WITH_ALL      = 7;
-
-    const SOURCE_MAP_NONE   = 0;
-    const SOURCE_MAP_INLINE = 1;
-    const SOURCE_MAP_FILE   = 2;
-
-    /**
-     * @var array
-     */
-    protected static $operatorNames = [
-        '+'   => 'add',
-        '-'   => 'sub',
-        '*'   => 'mul',
-        '/'   => 'div',
-        '%'   => 'mod',
-
-        '=='  => 'eq',
-        '!='  => 'neq',
-        '<'   => 'lt',
-        '>'   => 'gt',
-
-        '<='  => 'lte',
-        '>='  => 'gte',
-        '<=>' => 'cmp',
-    ];
-
-    /**
-     * @var array
-     */
-    protected static $namespaces = [
-        'special'  => '%',
-        'mixin'    => '@',
-        'function' => '^',
-    ];
-
-    public static $true         = [Type::T_KEYWORD, 'true'];
-    public static $false        = [Type::T_KEYWORD, 'false'];
-    public static $NaN          = [Type::T_KEYWORD, 'NaN'];
-    public static $Infinity     = [Type::T_KEYWORD, 'Infinity'];
-    public static $null         = [Type::T_NULL];
-    public static $nullString   = [Type::T_STRING, '', []];
-    public static $defaultValue = [Type::T_KEYWORD, ''];
-    public static $selfSelector = [Type::T_SELF];
-    public static $emptyList    = [Type::T_LIST, '', []];
-    public static $emptyMap     = [Type::T_MAP, [], []];
-    public static $emptyString  = [Type::T_STRING, '"', []];
-    public static $with         = [Type::T_KEYWORD, 'with'];
-    public static $without      = [Type::T_KEYWORD, 'without'];
-
-    protected $importPaths = [''];
-    protected $importCache = [];
-    protected $importedFiles = [];
-    protected $userFunctions = [];
-    protected $registeredVars = [];
-    protected $registeredFeatures = [
-        'extend-selector-pseudoclass' => false,
-        'at-error'                    => true,
-        'units-level-3'               => false,
-        'global-variable-shadowing'   => false,
-    ];
-
-    protected $encoding = null;
-    protected $lineNumberStyle = null;
-
-    protected $sourceMap = self::SOURCE_MAP_NONE;
-    protected $sourceMapOptions = [];
-
-    /**
-     * @var string|\ScssPhp\ScssPhp\Formatter
-     */
-    protected $formatter = 'ScssPhp\ScssPhp\Formatter\Nested';
-
-    protected $rootEnv;
-    protected $rootBlock;
-
-    /**
-     * @var \ScssPhp\ScssPhp\Compiler\Environment
-     */
-    protected $env;
-    protected $scope;
-    protected $storeEnv;
-    protected $charsetSeen;
-    protected $sourceNames;
-
-    protected $cache;
-
-    protected $indentLevel;
-    protected $extends;
-    protected $extendsMap;
-    protected $parsedFiles;
-    protected $parser;
-    protected $sourceIndex;
-    protected $sourceLine;
-    protected $sourceColumn;
-    protected $stderr;
-    protected $shouldEvaluate;
-    protected $ignoreErrors;
-    protected $ignoreCallStackMessage = false;
-
-    protected $callStack = [];
-
-    /**
-     * Constructor
-     *
-     * @param array|null $cacheOptions
-     */
-    public function __construct($cacheOptions = null)
-    {
-        $this->parsedFiles = [];
-        $this->sourceNames = [];
-
-        if ($cacheOptions) {
-            $this->cache = new Cache($cacheOptions);
-        }
-
-        $this->stderr = fopen('php://stderr', 'w');
-    }
-
-    /**
-     * Get compiler options
-     *
-     * @return array
-     */
-    public function getCompileOptions()
-    {
-        $options = [
-            'importPaths'        => $this->importPaths,
-            'registeredVars'     => $this->registeredVars,
-            'registeredFeatures' => $this->registeredFeatures,
-            'encoding'           => $this->encoding,
-            'sourceMap'          => serialize($this->sourceMap),
-            'sourceMapOptions'   => $this->sourceMapOptions,
-            'formatter'          => $this->formatter,
-        ];
-
-        return $options;
-    }
-
-    /**
-     * Set an alternative error output stream, for testing purpose only
-     *
-     * @param resource $handle
-     */
-    public function setErrorOuput($handle)
-    {
-        $this->stderr = $handle;
-    }
-
-    /**
-     * Compile scss
-     *
-     * @api
-     *
-     * @param string $code
-     * @param string $path
-     *
-     * @return string
-     */
-    public function compile($code, $path = null)
-    {
-        if ($this->cache) {
-            $cacheKey       = ($path ? $path : '(stdin)') . ':' . md5($code);
-            $compileOptions = $this->getCompileOptions();
-            $cache          = $this->cache->getCache('compile', $cacheKey, $compileOptions);
-
-            if (\is_array($cache) && isset($cache['dependencies']) && isset($cache['out'])) {
-                // check if any dependency file changed before accepting the cache
-                foreach ($cache['dependencies'] as $file => $mtime) {
-                    if (! is_file($file) || filemtime($file) !== $mtime) {
-                        unset($cache);
-                        break;
-                    }
-                }
-
-                if (isset($cache)) {
-                    return $cache['out'];
-                }
-            }
-        }
-
-
-        $this->indentLevel    = -1;
-        $this->extends        = [];
-        $this->extendsMap     = [];
-        $this->sourceIndex    = null;
-        $this->sourceLine     = null;
-        $this->sourceColumn   = null;
-        $this->env            = null;
-        $this->scope          = null;
-        $this->storeEnv       = null;
-        $this->charsetSeen    = null;
-        $this->shouldEvaluate = null;
-        $this->ignoreCallStackMessage = false;
-
-        $this->parser = $this->parserFactory($path);
-        $tree         = $this->parser->parse($code);
-        $this->parser = null;
-
-        $this->formatter = new $this->formatter();
-        $this->rootBlock = null;
-        $this->rootEnv   = $this->pushEnv($tree);
-
-        $this->injectVariables($this->registeredVars);
-        $this->compileRoot($tree);
-        $this->popEnv();
-
-        $sourceMapGenerator = null;
-
-        if ($this->sourceMap) {
-            if (\is_object($this->sourceMap) && $this->sourceMap instanceof SourceMapGenerator) {
-                $sourceMapGenerator = $this->sourceMap;
-                $this->sourceMap = self::SOURCE_MAP_FILE;
-            } elseif ($this->sourceMap !== self::SOURCE_MAP_NONE) {
-                $sourceMapGenerator = new SourceMapGenerator($this->sourceMapOptions);
-            }
-        }
-
-        $out = $this->formatter->format($this->scope, $sourceMapGenerator);
-
-        if (! empty($out) && $this->sourceMap && $this->sourceMap !== self::SOURCE_MAP_NONE) {
-            $sourceMap    = $sourceMapGenerator->generateJson();
-            $sourceMapUrl = null;
-
-            switch ($this->sourceMap) {
-                case self::SOURCE_MAP_INLINE:
-                    $sourceMapUrl = sprintf('data:application/json,%s', Util::encodeURIComponent($sourceMap));
-                    break;
-
-                case self::SOURCE_MAP_FILE:
-                    $sourceMapUrl = $sourceMapGenerator->saveMap($sourceMap);
-                    break;
-            }
-
-            $out .= sprintf('/*# sourceMappingURL=%s */', $sourceMapUrl);
-        }
-
-        if ($this->cache && isset($cacheKey) && isset($compileOptions)) {
-            $v = [
-                'dependencies' => $this->getParsedFiles(),
-                'out' => &$out,
-            ];
-
-            $this->cache->setCache('compile', $cacheKey, $v, $compileOptions);
-        }
-
-        return $out;
-    }
-
-    /**
-     * Instantiate parser
-     *
-     * @param string $path
-     *
-     * @return \ScssPhp\ScssPhp\Parser
-     */
-    protected function parserFactory($path)
-    {
-        // https://sass-lang.com/documentation/at-rules/import
-        // CSS files imported by Sass don’t allow any special Sass features.
-        // In order to make sure authors don’t accidentally write Sass in their CSS,
-        // all Sass features that aren’t also valid CSS will produce errors.
-        // Otherwise, the CSS will be rendered as-is. It can even be extended!
-        $cssOnly = false;
-
-        if (substr($path, '-4') === '.css') {
-            $cssOnly = true;
-        }
-
-        $parser = new Parser($path, \count($this->sourceNames), $this->encoding, $this->cache, $cssOnly);
-
-        $this->sourceNames[] = $path;
-        $this->addParsedFile($path);
-
-        return $parser;
-    }
-
-    /**
-     * Is self extend?
-     *
-     * @param array $target
-     * @param array $origin
-     *
-     * @return boolean
-     */
-    protected function isSelfExtend($target, $origin)
-    {
-        foreach ($origin as $sel) {
-            if (\in_array($target, $sel)) {
-                return true;
-            }
-        }
-
-        return false;
-    }
-
-    /**
-     * Push extends
-     *
-     * @param array      $target
-     * @param array      $origin
-     * @param array|null $block
-     */
-    protected function pushExtends($target, $origin, $block)
-    {
-        $i = \count($this->extends);
-        $this->extends[] = [$target, $origin, $block];
-
-        foreach ($target as $part) {
-            if (isset($this->extendsMap[$part])) {
-                $this->extendsMap[$part][] = $i;
-            } else {
-                $this->extendsMap[$part] = [$i];
-            }
-        }
-    }
-
-    /**
-     * Make output block
-     *
-     * @param string $type
-     * @param array  $selectors
-     *
-     * @return \ScssPhp\ScssPhp\Formatter\OutputBlock
-     */
-    protected function makeOutputBlock($type, $selectors = null)
-    {
-        $out = new OutputBlock();
-        $out->type      = $type;
-        $out->lines     = [];
-        $out->children  = [];
-        $out->parent    = $this->scope;
-        $out->selectors = $selectors;
-        $out->depth     = $this->env->depth;
-
-        if ($this->env->block instanceof Block) {
-            $out->sourceName   = $this->env->block->sourceName;
-            $out->sourceLine   = $this->env->block->sourceLine;
-            $out->sourceColumn = $this->env->block->sourceColumn;
-        } else {
-            $out->sourceName   = null;
-            $out->sourceLine   = null;
-            $out->sourceColumn = null;
-        }
-
-        return $out;
-    }
-
-    /**
-     * Compile root
-     *
-     * @param \ScssPhp\ScssPhp\Block $rootBlock
-     */
-    protected function compileRoot(Block $rootBlock)
-    {
-        $this->rootBlock = $this->scope = $this->makeOutputBlock(Type::T_ROOT);
-
-        $this->compileChildrenNoReturn($rootBlock->children, $this->scope);
-        $this->flattenSelectors($this->scope);
-        $this->missingSelectors();
-    }
-
-    /**
-     * Report missing selectors
-     */
-    protected function missingSelectors()
-    {
-        foreach ($this->extends as $extend) {
-            if (isset($extend[3])) {
-                continue;
-            }
-
-            list($target, $origin, $block) = $extend;
-
-            // ignore if !optional
-            if ($block[2]) {
-                continue;
-            }
-
-            $target = implode(' ', $target);
-            $origin = $this->collapseSelectors($origin);
-
-            $this->sourceLine = $block[Parser::SOURCE_LINE];
-            throw $this->error("\"$origin\" failed to @extend \"$target\". The selector \"$target\" was not found.");
-        }
-    }
-
-    /**
-     * Flatten selectors
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
-     * @param string                                 $parentKey
-     */
-    protected function flattenSelectors(OutputBlock $block, $parentKey = null)
-    {
-        if ($block->selectors) {
-            $selectors = [];
-
-            foreach ($block->selectors as $s) {
-                $selectors[] = $s;
-
-                if (! \is_array($s)) {
-                    continue;
-                }
-
-                // check extends
-                if (! empty($this->extendsMap)) {
-                    $this->matchExtends($s, $selectors);
-
-                    // remove duplicates
-                    array_walk($selectors, function (&$value) {
-                        $value = serialize($value);
-                    });
-
-                    $selectors = array_unique($selectors);
-
-                    array_walk($selectors, function (&$value) {
-                        $value = unserialize($value);
-                    });
-                }
-            }
-
-            $block->selectors = [];
-            $placeholderSelector = false;
-
-            foreach ($selectors as $selector) {
-                if ($this->hasSelectorPlaceholder($selector)) {
-                    $placeholderSelector = true;
-                    continue;
-                }
-
-                $block->selectors[] = $this->compileSelector($selector);
-            }
-
-            if ($placeholderSelector && 0 === \count($block->selectors) && null !== $parentKey) {
-                unset($block->parent->children[$parentKey]);
-
-                return;
-            }
-        }
-
-        foreach ($block->children as $key => $child) {
-            $this->flattenSelectors($child, $key);
-        }
-    }
-
-    /**
-     * Glue parts of :not( or :nth-child( ... that are in general splitted in selectors parts
-     *
-     * @param array $parts
-     *
-     * @return array
-     */
-    protected function glueFunctionSelectors($parts)
-    {
-        $new = [];
-
-        foreach ($parts as $part) {
-            if (\is_array($part)) {
-                $part = $this->glueFunctionSelectors($part);
-                $new[] = $part;
-            } else {
-                // a selector part finishing with a ) is the last part of a :not( or :nth-child(
-                // and need to be joined to this
-                if (
-                    \count($new) && \is_string($new[\count($new) - 1]) &&
-                    \strlen($part) && substr($part, -1) === ')' && strpos($part, '(') === false
-                ) {
-                    while (\count($new) > 1 && substr($new[\count($new) - 1], -1) !== '(') {
-                        $part = array_pop($new) . $part;
-                    }
-                    $new[\count($new) - 1] .= $part;
-                } else {
-                    $new[] = $part;
-                }
-            }
-        }
-
-        return $new;
-    }
-
-    /**
-     * Match extends
-     *
-     * @param array   $selector
-     * @param array   $out
-     * @param integer $from
-     * @param boolean $initial
-     */
-    protected function matchExtends($selector, &$out, $from = 0, $initial = true)
-    {
-        static $partsPile = [];
-        $selector = $this->glueFunctionSelectors($selector);
-
-        if (\count($selector) == 1 && \in_array(reset($selector), $partsPile)) {
-            return;
-        }
-
-        $outRecurs = [];
-
-        foreach ($selector as $i => $part) {
-            if ($i < $from) {
-                continue;
-            }
-
-            // check that we are not building an infinite loop of extensions
-            // if the new part is just including a previous part don't try to extend anymore
-            if (\count($part) > 1) {
-                foreach ($partsPile as $previousPart) {
-                    if (! \count(array_diff($previousPart, $part))) {
-                        continue 2;
-                    }
-                }
-            }
-
-            $partsPile[] = $part;
-
-            if ($this->matchExtendsSingle($part, $origin, $initial)) {
-                $after       = \array_slice($selector, $i + 1);
-                $before      = \array_slice($selector, 0, $i);
-                list($before, $nonBreakableBefore) = $this->extractRelationshipFromFragment($before);
-
-                foreach ($origin as $new) {
-                    $k = 0;
-
-                    // remove shared parts
-                    if (\count($new) > 1) {
-                        while ($k < $i && isset($new[$k]) && $selector[$k] === $new[$k]) {
-                            $k++;
-                        }
-                    }
-
-                    if (\count($nonBreakableBefore) && $k === \count($new)) {
-                        $k--;
-                    }
-
-                    $replacement = [];
-                    $tempReplacement = $k > 0 ? \array_slice($new, $k) : $new;
-
-                    for ($l = \count($tempReplacement) - 1; $l >= 0; $l--) {
-                        $slice = [];
-
-                        foreach ($tempReplacement[$l] as $chunk) {
-                            if (! \in_array($chunk, $slice)) {
-                                $slice[] = $chunk;
-                            }
-                        }
-
-                        array_unshift($replacement, $slice);
-
-                        if (! $this->isImmediateRelationshipCombinator(end($slice))) {
-                            break;
-                        }
-                    }
-
-                    $afterBefore = $l != 0 ? \array_slice($tempReplacement, 0, $l) : [];
-
-                    // Merge shared direct relationships.
-                    $mergedBefore = $this->mergeDirectRelationships($afterBefore, $nonBreakableBefore);
-
-                    $result = array_merge(
-                        $before,
-                        $mergedBefore,
-                        $replacement,
-                        $after
-                    );
-
-                    if ($result === $selector) {
-                        continue;
-                    }
-
-                    $this->pushOrMergeExtentedSelector($out, $result);
-
-                    // recursively check for more matches
-                    $startRecurseFrom = \count($before) + min(\count($nonBreakableBefore), \count($mergedBefore));
-
-                    if (\count($origin) > 1) {
-                        $this->matchExtends($result, $out, $startRecurseFrom, false);
-                    } else {
-                        $this->matchExtends($result, $outRecurs, $startRecurseFrom, false);
-                    }
-
-                    // selector sequence merging
-                    if (! empty($before) && \count($new) > 1) {
-                        $preSharedParts = $k > 0 ? \array_slice($before, 0, $k) : [];
-                        $postSharedParts = $k > 0 ? \array_slice($before, $k) : $before;
-
-                        list($betweenSharedParts, $nonBreakabl2) = $this->extractRelationshipFromFragment($afterBefore);
-
-                        $result2 = array_merge(
-                            $preSharedParts,
-                            $betweenSharedParts,
-                            $postSharedParts,
-                            $nonBreakabl2,
-                            $nonBreakableBefore,
-                            $replacement,
-                            $after
-                        );
-
-                        $this->pushOrMergeExtentedSelector($out, $result2);
-                    }
-                }
-            }
-            array_pop($partsPile);
-        }
-
-        while (\count($outRecurs)) {
-            $result = array_shift($outRecurs);
-            $this->pushOrMergeExtentedSelector($out, $result);
-        }
-    }
-
-    /**
-     * Test a part for being a pseudo selector
-     *
-     * @param string $part
-     * @param array  $matches
-     *
-     * @return boolean
-     */
-    protected function isPseudoSelector($part, &$matches)
-    {
-        if (
-            strpos($part, ':') === 0 &&
-            preg_match(",^::?([\w-]+)\((.+)\)$,", $part, $matches)
-        ) {
-            return true;
-        }
-
-        return false;
-    }
-
-    /**
-     * Push extended selector except if
-     *  - this is a pseudo selector
-     *  - same as previous
-     *  - in a white list
-     * in this case we merge the pseudo selector content
-     *
-     * @param array $out
-     * @param array $extended
-     */
-    protected function pushOrMergeExtentedSelector(&$out, $extended)
-    {
-        if (\count($out) && \count($extended) === 1 && \count(reset($extended)) === 1) {
-            $single = reset($extended);
-            $part = reset($single);
-
-            if (
-                $this->isPseudoSelector($part, $matchesExtended) &&
-                \in_array($matchesExtended[1], [ 'slotted' ])
-            ) {
-                $prev = end($out);
-                $prev = $this->glueFunctionSelectors($prev);
-
-                if (\count($prev) === 1 && \count(reset($prev)) === 1) {
-                    $single = reset($prev);
-                    $part = reset($single);
-
-                    if (
-                        $this->isPseudoSelector($part, $matchesPrev) &&
-                        $matchesPrev[1] === $matchesExtended[1]
-                    ) {
-                        $extended = explode($matchesExtended[1] . '(', $matchesExtended[0], 2);
-                        $extended[1] = $matchesPrev[2] . ', ' . $extended[1];
-                        $extended = implode($matchesExtended[1] . '(', $extended);
-                        $extended = [ [ $extended ]];
-                        array_pop($out);
-                    }
-                }
-            }
-        }
-        $out[] = $extended;
-    }
-
-    /**
-     * Match extends single
-     *
-     * @param array   $rawSingle
-     * @param array   $outOrigin
-     * @param boolean $initial
-     *
-     * @return boolean
-     */
-    protected function matchExtendsSingle($rawSingle, &$outOrigin, $initial = true)
-    {
-        $counts = [];
-        $single = [];
-
-        // simple usual cases, no need to do the whole trick
-        if (\in_array($rawSingle, [['>'],['+'],['~']])) {
-            return false;
-        }
-
-        foreach ($rawSingle as $part) {
-            // matches Number
-            if (! \is_string($part)) {
-                return false;
-            }
-
-            if (! preg_match('/^[\[.:#%]/', $part) && \count($single)) {
-                $single[\count($single) - 1] .= $part;
-            } else {
-                $single[] = $part;
-            }
-        }
-
-        $extendingDecoratedTag = false;
-
-        if (\count($single) > 1) {
-            $matches = null;
-            $extendingDecoratedTag = preg_match('/^[a-z0-9]+$/i', $single[0], $matches) ? $matches[0] : false;
-        }
-
-        $outOrigin = [];
-        $found = false;
-
-        foreach ($single as $k => $part) {
-            if (isset($this->extendsMap[$part])) {
-                foreach ($this->extendsMap[$part] as $idx) {
-                    $counts[$idx] = isset($counts[$idx]) ? $counts[$idx] + 1 : 1;
-                }
-            }
-
-            if (
-                $initial &&
-                $this->isPseudoSelector($part, $matches) &&
-                ! \in_array($matches[1], [ 'not' ])
-            ) {
-                $buffer    = $matches[2];
-                $parser    = $this->parserFactory(__METHOD__);
-
-                if ($parser->parseSelector($buffer, $subSelectors)) {
-                    foreach ($subSelectors as $ksub => $subSelector) {
-                        $subExtended = [];
-                        $this->matchExtends($subSelector, $subExtended, 0, false);
-
-                        if ($subExtended) {
-                            $subSelectorsExtended = $subSelectors;
-                            $subSelectorsExtended[$ksub] = $subExtended;
-
-                            foreach ($subSelectorsExtended as $ksse => $sse) {
-                                $subSelectorsExtended[$ksse] = $this->collapseSelectors($sse);
-                            }
-
-                            $subSelectorsExtended = implode(', ', $subSelectorsExtended);
-                            $singleExtended = $single;
-                            $singleExtended[$k] = str_replace('(' . $buffer . ')', "($subSelectorsExtended)", $part);
-                            $outOrigin[] = [ $singleExtended ];
-                            $found = true;
-                        }
-                    }
-                }
-            }
-        }
-
-        foreach ($counts as $idx => $count) {
-            list($target, $origin, /* $block */) = $this->extends[$idx];
-
-            $origin = $this->glueFunctionSelectors($origin);
-
-            // check count
-            if ($count !== \count($target)) {
-                continue;
-            }
-
-            $this->extends[$idx][3] = true;
-
-            $rem = array_diff($single, $target);
-
-            foreach ($origin as $j => $new) {
-                // prevent infinite loop when target extends itself
-                if ($this->isSelfExtend($single, $origin) && ! $initial) {
-                    return false;
-                }
-
-                $replacement = end($new);
-
-                // Extending a decorated tag with another tag is not possible.
-                if (
-                    $extendingDecoratedTag && $replacement[0] != $extendingDecoratedTag &&
-                    preg_match('/^[a-z0-9]+$/i', $replacement[0])
-                ) {
-                    unset($origin[$j]);
-                    continue;
-                }
-
-                $combined = $this->combineSelectorSingle($replacement, $rem);
-
-                if (\count(array_diff($combined, $origin[$j][\count($origin[$j]) - 1]))) {
-                    $origin[$j][\count($origin[$j]) - 1] = $combined;
-                }
-            }
-
-            $outOrigin = array_merge($outOrigin, $origin);
-
-            $found = true;
-        }
-
-        return $found;
-    }
-
-    /**
-     * Extract a relationship from the fragment.
-     *
-     * When extracting the last portion of a selector we will be left with a
-     * fragment which may end with a direction relationship combinator. This
-     * method will extract the relationship fragment and return it along side
-     * the rest.
-     *
-     * @param array $fragment The selector fragment maybe ending with a direction relationship combinator.
-     *
-     * @return array The selector without the relationship fragment if any, the relationship fragment.
-     */
-    protected function extractRelationshipFromFragment(array $fragment)
-    {
-        $parents = [];
-        $children = [];
-
-        $j = $i = \count($fragment);
-
-        for (;;) {
-            $children = $j != $i ? \array_slice($fragment, $j, $i - $j) : [];
-            $parents  = \array_slice($fragment, 0, $j);
-            $slice    = end($parents);
-
-            if (empty($slice) || ! $this->isImmediateRelationshipCombinator($slice[0])) {
-                break;
-            }
-
-            $j -= 2;
-        }
-
-        return [$parents, $children];
-    }
-
-    /**
-     * Combine selector single
-     *
-     * @param array $base
-     * @param array $other
-     *
-     * @return array
-     */
-    protected function combineSelectorSingle($base, $other)
-    {
-        $tag    = [];
-        $out    = [];
-        $wasTag = false;
-        $pseudo = [];
-
-        while (\count($other) && strpos(end($other), ':') === 0) {
-            array_unshift($pseudo, array_pop($other));
-        }
-
-        foreach ([array_reverse($base), array_reverse($other)] as $single) {
-            $rang = count($single);
-
-            foreach ($single as $part) {
-                if (preg_match('/^[\[:]/', $part)) {
-                    $out[] = $part;
-                    $wasTag = false;
-                } elseif (preg_match('/^[\.#]/', $part)) {
-                    array_unshift($out, $part);
-                    $wasTag = false;
-                } elseif (preg_match('/^[^_-]/', $part) && $rang === 1) {
-                    $tag[] = $part;
-                    $wasTag = true;
-                } elseif ($wasTag) {
-                    $tag[\count($tag) - 1] .= $part;
-                } else {
-                    array_unshift($out, $part);
-                }
-                $rang--;
-            }
-        }
-
-        if (\count($tag)) {
-            array_unshift($out, $tag[0]);
-        }
-
-        while (\count($pseudo)) {
-            $out[] = array_shift($pseudo);
-        }
-
-        return $out;
-    }
-
-    /**
-     * Compile media
-     *
-     * @param \ScssPhp\ScssPhp\Block $media
-     */
-    protected function compileMedia(Block $media)
-    {
-        $this->pushEnv($media);
-
-        $mediaQueries = $this->compileMediaQuery($this->multiplyMedia($this->env));
-
-        if (! empty($mediaQueries) && $mediaQueries) {
-            $previousScope = $this->scope;
-            $parentScope = $this->mediaParent($this->scope);
-
-            foreach ($mediaQueries as $mediaQuery) {
-                $this->scope = $this->makeOutputBlock(Type::T_MEDIA, [$mediaQuery]);
-
-                $parentScope->children[] = $this->scope;
-                $parentScope = $this->scope;
-            }
-
-            // top level properties in a media cause it to be wrapped
-            $needsWrap = false;
-
-            foreach ($media->children as $child) {
-                $type = $child[0];
-
-                if (
-                    $type !== Type::T_BLOCK &&
-                    $type !== Type::T_MEDIA &&
-                    $type !== Type::T_DIRECTIVE &&
-                    $type !== Type::T_IMPORT
-                ) {
-                    $needsWrap = true;
-                    break;
-                }
-            }
-
-            if ($needsWrap) {
-                $wrapped = new Block();
-                $wrapped->sourceName   = $media->sourceName;
-                $wrapped->sourceIndex  = $media->sourceIndex;
-                $wrapped->sourceLine   = $media->sourceLine;
-                $wrapped->sourceColumn = $media->sourceColumn;
-                $wrapped->selectors    = [];
-                $wrapped->comments     = [];
-                $wrapped->parent       = $media;
-                $wrapped->children     = $media->children;
-
-                $media->children = [[Type::T_BLOCK, $wrapped]];
-
-                if (isset($this->lineNumberStyle)) {
-                    $annotation = $this->makeOutputBlock(Type::T_COMMENT);
-                    $annotation->depth = 0;
-
-                    $file = $this->sourceNames[$media->sourceIndex];
-                    $line = $media->sourceLine;
-
-                    switch ($this->lineNumberStyle) {
-                        case static::LINE_COMMENTS:
-                            $annotation->lines[] = '/* line ' . $line
-                                                 . ($file ? ', ' . $file : '')
-                                                 . ' */';
-                            break;
-
-                        case static::DEBUG_INFO:
-                            $annotation->lines[] = '@media -sass-debug-info{'
-                                                 . ($file ? 'filename{font-family:"' . $file . '"}' : '')
-                                                 . 'line{font-family:' . $line . '}}';
-                            break;
-                    }
-
-                    $this->scope->children[] = $annotation;
-                }
-            }
-
-            $this->compileChildrenNoReturn($media->children, $this->scope);
-
-            $this->scope = $previousScope;
-        }
-
-        $this->popEnv();
-    }
-
-    /**
-     * Media parent
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
-     *
-     * @return \ScssPhp\ScssPhp\Formatter\OutputBlock
-     */
-    protected function mediaParent(OutputBlock $scope)
-    {
-        while (! empty($scope->parent)) {
-            if (! empty($scope->type) && $scope->type !== Type::T_MEDIA) {
-                break;
-            }
-
-            $scope = $scope->parent;
-        }
-
-        return $scope;
-    }
-
-    /**
-     * Compile directive
-     *
-     * @param \ScssPhp\ScssPhp\Block|array $block
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     */
-    protected function compileDirective($directive, OutputBlock $out)
-    {
-        if (\is_array($directive)) {
-            $s = '@' . $directive[0];
-
-            if (! empty($directive[1])) {
-                $s .= ' ' . $this->compileValue($directive[1]);
-            }
-
-            $this->appendRootDirective($s . ';', $out);
-        } else {
-            $s = '@' . $directive->name;
-
-            if (! empty($directive->value)) {
-                $s .= ' ' . $this->compileValue($directive->value);
-            }
-
-            if ($directive->name === 'keyframes' || substr($directive->name, -10) === '-keyframes') {
-                $this->compileKeyframeBlock($directive, [$s]);
-            } else {
-                $this->compileNestedBlock($directive, [$s]);
-            }
-        }
-    }
-
-    /**
-     * Compile at-root
-     *
-     * @param \ScssPhp\ScssPhp\Block $block
-     */
-    protected function compileAtRoot(Block $block)
-    {
-        $env     = $this->pushEnv($block);
-        $envs    = $this->compactEnv($env);
-        list($with, $without) = $this->compileWith(isset($block->with) ? $block->with : null);
-
-        // wrap inline selector
-        if ($block->selector) {
-            $wrapped = new Block();
-            $wrapped->sourceName   = $block->sourceName;
-            $wrapped->sourceIndex  = $block->sourceIndex;
-            $wrapped->sourceLine   = $block->sourceLine;
-            $wrapped->sourceColumn = $block->sourceColumn;
-            $wrapped->selectors    = $block->selector;
-            $wrapped->comments     = [];
-            $wrapped->parent       = $block;
-            $wrapped->children     = $block->children;
-            $wrapped->selfParent   = $block->selfParent;
-
-            $block->children = [[Type::T_BLOCK, $wrapped]];
-            $block->selector = null;
-        }
-
-        $selfParent = $block->selfParent;
-
-        if (
-            ! $block->selfParent->selectors &&
-            isset($block->parent) && $block->parent &&
-            isset($block->parent->selectors) && $block->parent->selectors
-        ) {
-            $selfParent = $block->parent;
-        }
-
-        $this->env = $this->filterWithWithout($envs, $with, $without);
-
-        $saveScope   = $this->scope;
-        $this->scope = $this->filterScopeWithWithout($saveScope, $with, $without);
-
-        // propagate selfParent to the children where they still can be useful
-        $this->compileChildrenNoReturn($block->children, $this->scope, $selfParent);
-
-        $this->scope = $this->completeScope($this->scope, $saveScope);
-        $this->scope = $saveScope;
-        $this->env   = $this->extractEnv($envs);
-
-        $this->popEnv();
-    }
-
-    /**
-     * Filter at-root scope depending of with/without option
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
-     * @param array                                  $with
-     * @param array                                  $without
-     *
-     * @return mixed
-     */
-    protected function filterScopeWithWithout($scope, $with, $without)
-    {
-        $filteredScopes = [];
-        $childStash = [];
-
-        if ($scope->type === TYPE::T_ROOT) {
-            return $scope;
-        }
-
-        // start from the root
-        while ($scope->parent && $scope->parent->type !== TYPE::T_ROOT) {
-            array_unshift($childStash, $scope);
-            $scope = $scope->parent;
-        }
-
-        for (;;) {
-            if (! $scope) {
-                break;
-            }
-
-            if ($this->isWith($scope, $with, $without)) {
-                $s = clone $scope;
-                $s->children = [];
-                $s->lines    = [];
-                $s->parent   = null;
-
-                if ($s->type !== Type::T_MEDIA && $s->type !== Type::T_DIRECTIVE) {
-                    $s->selectors = [];
-                }
-
-                $filteredScopes[] = $s;
-            }
-
-            if (\count($childStash)) {
-                $scope = array_shift($childStash);
-            } elseif ($scope->children) {
-                $scope = end($scope->children);
-            } else {
-                $scope = null;
-            }
-        }
-
-        if (! \count($filteredScopes)) {
-            return $this->rootBlock;
-        }
-
-        $newScope = array_shift($filteredScopes);
-        $newScope->parent = $this->rootBlock;
-
-        $this->rootBlock->children[] = $newScope;
-
-        $p = &$newScope;
-
-        while (\count($filteredScopes)) {
-            $s = array_shift($filteredScopes);
-            $s->parent = $p;
-            $p->children[] = $s;
-            $newScope = &$p->children[0];
-            $p = &$p->children[0];
-        }
-
-        return $newScope;
-    }
-
-    /**
-     * found missing selector from a at-root compilation in the previous scope
-     * (if at-root is just enclosing a property, the selector is in the parent tree)
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $previousScope
-     *
-     * @return mixed
-     */
-    protected function completeScope($scope, $previousScope)
-    {
-        if (! $scope->type && (! $scope->selectors || ! \count($scope->selectors)) && \count($scope->lines)) {
-            $scope->selectors = $this->findScopeSelectors($previousScope, $scope->depth);
-        }
-
-        if ($scope->children) {
-            foreach ($scope->children as $k => $c) {
-                $scope->children[$k] = $this->completeScope($c, $previousScope);
-            }
-        }
-
-        return $scope;
-    }
-
-    /**
-     * Find a selector by the depth node in the scope
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
-     * @param integer                                $depth
-     *
-     * @return array
-     */
-    protected function findScopeSelectors($scope, $depth)
-    {
-        if ($scope->depth === $depth && $scope->selectors) {
-            return $scope->selectors;
-        }
-
-        if ($scope->children) {
-            foreach (array_reverse($scope->children) as $c) {
-                if ($s = $this->findScopeSelectors($c, $depth)) {
-                    return $s;
-                }
-            }
-        }
-
-        return [];
-    }
-
-    /**
-     * Compile @at-root's with: inclusion / without: exclusion into 2 lists uses to filter scope/env later
-     *
-     * @param array $withCondition
-     *
-     * @return array
-     */
-    protected function compileWith($withCondition)
-    {
-        // just compile what we have in 2 lists
-        $with = [];
-        $without = ['rule' => true];
-
-        if ($withCondition) {
-            if ($withCondition[0] === Type::T_INTERPOLATE) {
-                $w = $this->compileValue($withCondition);
-
-                $buffer = "($w)";
-                $parser = $this->parserFactory(__METHOD__);
-
-                if ($parser->parseValue($buffer, $reParsedWith)) {
-                    $withCondition = $reParsedWith;
-                }
-            }
-
-            if ($this->libMapHasKey([$withCondition, static::$with])) {
-                $without = []; // cancel the default
-                $list = $this->coerceList($this->libMapGet([$withCondition, static::$with]));
-
-                foreach ($list[2] as $item) {
-                    $keyword = $this->compileStringContent($this->coerceString($item));
-
-                    $with[$keyword] = true;
-                }
-            }
-
-            if ($this->libMapHasKey([$withCondition, static::$without])) {
-                $without = []; // cancel the default
-                $list = $this->coerceList($this->libMapGet([$withCondition, static::$without]));
-
-                foreach ($list[2] as $item) {
-                    $keyword = $this->compileStringContent($this->coerceString($item));
-
-                    $without[$keyword] = true;
-                }
-            }
-        }
-
-        return [$with, $without];
-    }
-
-    /**
-     * Filter env stack
-     *
-     * @param array $envs
-     * @param array $with
-     * @param array $without
-     *
-     * @return \ScssPhp\ScssPhp\Compiler\Environment
-     */
-    protected function filterWithWithout($envs, $with, $without)
-    {
-        $filtered = [];
-
-        foreach ($envs as $e) {
-            if ($e->block && ! $this->isWith($e->block, $with, $without)) {
-                $ec = clone $e;
-                $ec->block     = null;
-                $ec->selectors = [];
-
-                $filtered[] = $ec;
-            } else {
-                $filtered[] = $e;
-            }
-        }
-
-        return $this->extractEnv($filtered);
-    }
-
-    /**
-     * Filter WITH rules
-     *
-     * @param \ScssPhp\ScssPhp\Block|\ScssPhp\ScssPhp\Formatter\OutputBlock $block
-     * @param array                                                         $with
-     * @param array                                                         $without
-     *
-     * @return boolean
-     */
-    protected function isWith($block, $with, $without)
-    {
-        if (isset($block->type)) {
-            if ($block->type === Type::T_MEDIA) {
-                return $this->testWithWithout('media', $with, $without);
-            }
-
-            if ($block->type === Type::T_DIRECTIVE) {
-                if (isset($block->name)) {
-                    return $this->testWithWithout($block->name, $with, $without);
-                } elseif (isset($block->selectors) && preg_match(',@(\w+),ims', json_encode($block->selectors), $m)) {
-                    return $this->testWithWithout($m[1], $with, $without);
-                } else {
-                    return $this->testWithWithout('???', $with, $without);
-                }
-            }
-        } elseif (isset($block->selectors)) {
-            // a selector starting with number is a keyframe rule
-            if (\count($block->selectors)) {
-                $s = reset($block->selectors);
-
-                while (\is_array($s)) {
-                    $s = reset($s);
-                }
-
-                if (\is_object($s) && $s instanceof Node\Number) {
-                    return $this->testWithWithout('keyframes', $with, $without);
-                }
-            }
-
-            return $this->testWithWithout('rule', $with, $without);
-        }
-
-        return true;
-    }
-
-    /**
-     * Test a single type of block against with/without lists
-     *
-     * @param string $what
-     * @param array  $with
-     * @param array  $without
-     *
-     * @return boolean
-     *   true if the block should be kept, false to reject
-     */
-    protected function testWithWithout($what, $with, $without)
-    {
-        // if without, reject only if in the list (or 'all' is in the list)
-        if (\count($without)) {
-            return (isset($without[$what]) || isset($without['all'])) ? false : true;
-        }
-
-        // otherwise reject all what is not in the with list
-        return (isset($with[$what]) || isset($with['all'])) ? true : false;
-    }
-
-
-    /**
-     * Compile keyframe block
-     *
-     * @param \ScssPhp\ScssPhp\Block $block
-     * @param array                  $selectors
-     */
-    protected function compileKeyframeBlock(Block $block, $selectors)
-    {
-        $env = $this->pushEnv($block);
-
-        $envs = $this->compactEnv($env);
-
-        $this->env = $this->extractEnv(array_filter($envs, function (Environment $e) {
-            return ! isset($e->block->selectors);
-        }));
-
-        $this->scope = $this->makeOutputBlock($block->type, $selectors);
-        $this->scope->depth = 1;
-        $this->scope->parent->children[] = $this->scope;
-
-        $this->compileChildrenNoReturn($block->children, $this->scope);
-
-        $this->scope = $this->scope->parent;
-        $this->env   = $this->extractEnv($envs);
-
-        $this->popEnv();
-    }
-
-    /**
-     * Compile nested properties lines
-     *
-     * @param \ScssPhp\ScssPhp\Block                 $block
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     */
-    protected function compileNestedPropertiesBlock(Block $block, OutputBlock $out)
-    {
-        $prefix = $this->compileValue($block->prefix) . '-';
-
-        $nested = $this->makeOutputBlock($block->type);
-        $nested->parent = $out;
-
-        if ($block->hasValue) {
-            $nested->depth = $out->depth + 1;
-        }
-
-        $out->children[] = $nested;
-
-        foreach ($block->children as $child) {
-            switch ($child[0]) {
-                case Type::T_ASSIGN:
-                    array_unshift($child[1][2], $prefix);
-                    break;
-
-                case Type::T_NESTED_PROPERTY:
-                    array_unshift($child[1]->prefix[2], $prefix);
-                    break;
-            }
-
-            $this->compileChild($child, $nested);
-        }
-    }
-
-    /**
-     * Compile nested block
-     *
-     * @param \ScssPhp\ScssPhp\Block $block
-     * @param array                  $selectors
-     */
-    protected function compileNestedBlock(Block $block, $selectors)
-    {
-        $this->pushEnv($block);
-
-        $this->scope = $this->makeOutputBlock($block->type, $selectors);
-        $this->scope->parent->children[] = $this->scope;
-
-        // wrap assign children in a block
-        // except for @font-face
-        if ($block->type !== Type::T_DIRECTIVE || $block->name !== 'font-face') {
-            // need wrapping?
-            $needWrapping = false;
-
-            foreach ($block->children as $child) {
-                if ($child[0] === Type::T_ASSIGN) {
-                    $needWrapping = true;
-                    break;
-                }
-            }
-
-            if ($needWrapping) {
-                $wrapped = new Block();
-                $wrapped->sourceName   = $block->sourceName;
-                $wrapped->sourceIndex  = $block->sourceIndex;
-                $wrapped->sourceLine   = $block->sourceLine;
-                $wrapped->sourceColumn = $block->sourceColumn;
-                $wrapped->selectors    = [];
-                $wrapped->comments     = [];
-                $wrapped->parent       = $block;
-                $wrapped->children     = $block->children;
-                $wrapped->selfParent   = $block->selfParent;
-
-                $block->children = [[Type::T_BLOCK, $wrapped]];
-            }
-        }
-
-        $this->compileChildrenNoReturn($block->children, $this->scope);
-
-        $this->scope = $this->scope->parent;
-
-        $this->popEnv();
-    }
-
-    /**
-     * Recursively compiles a block.
-     *
-     * A block is analogous to a CSS block in most cases. A single SCSS document
-     * is encapsulated in a block when parsed, but it does not have parent tags
-     * so all of its children appear on the root level when compiled.
-     *
-     * Blocks are made up of selectors and children.
-     *
-     * The children of a block are just all the blocks that are defined within.
-     *
-     * Compiling the block involves pushing a fresh environment on the stack,
-     * and iterating through the props, compiling each one.
-     *
-     * @see Compiler::compileChild()
-     *
-     * @param \ScssPhp\ScssPhp\Block $block
-     */
-    protected function compileBlock(Block $block)
-    {
-        $env = $this->pushEnv($block);
-        $env->selectors = $this->evalSelectors($block->selectors);
-
-        $out = $this->makeOutputBlock(null);
-
-        if (isset($this->lineNumberStyle) && \count($env->selectors) && \count($block->children)) {
-            $annotation = $this->makeOutputBlock(Type::T_COMMENT);
-            $annotation->depth = 0;
-
-            $file = $this->sourceNames[$block->sourceIndex];
-            $line = $block->sourceLine;
-
-            switch ($this->lineNumberStyle) {
-                case static::LINE_COMMENTS:
-                    $annotation->lines[] = '/* line ' . $line
-                                         . ($file ? ', ' . $file : '')
-                                         . ' */';
-                    break;
-
-                case static::DEBUG_INFO:
-                    $annotation->lines[] = '@media -sass-debug-info{'
-                                         . ($file ? 'filename{font-family:"' . $file . '"}' : '')
-                                         . 'line{font-family:' . $line . '}}';
-                    break;
-            }
-
-            $this->scope->children[] = $annotation;
-        }
-
-        $this->scope->children[] = $out;
-
-        if (\count($block->children)) {
-            $out->selectors = $this->multiplySelectors($env, $block->selfParent);
-
-            // propagate selfParent to the children where they still can be useful
-            $selfParentSelectors = null;
-
-            if (isset($block->selfParent->selectors)) {
-                $selfParentSelectors = $block->selfParent->selectors;
-                $block->selfParent->selectors = $out->selectors;
-            }
-
-            $this->compileChildrenNoReturn($block->children, $out, $block->selfParent);
-
-            // and revert for the following children of the same block
-            if ($selfParentSelectors) {
-                $block->selfParent->selectors = $selfParentSelectors;
-            }
-        }
-
-        $this->popEnv();
-    }
-
-
-    /**
-     * Compile the value of a comment that can have interpolation
-     *
-     * @param array   $value
-     * @param boolean $pushEnv
-     *
-     * @return array|mixed|string
-     */
-    protected function compileCommentValue($value, $pushEnv = false)
-    {
-        $c = $value[1];
-
-        if (isset($value[2])) {
-            if ($pushEnv) {
-                $this->pushEnv();
-            }
-
-            $ignoreCallStackMessage = $this->ignoreCallStackMessage;
-            $this->ignoreCallStackMessage = true;
-
-            try {
-                $c = $this->compileValue($value[2]);
-            } catch (\Exception $e) {
-                // ignore error in comment compilation which are only interpolation
-            }
-
-            $this->ignoreCallStackMessage = $ignoreCallStackMessage;
-
-            if ($pushEnv) {
-                $this->popEnv();
-            }
-        }
-
-        return $c;
-    }
-
-    /**
-     * Compile root level comment
-     *
-     * @param array $block
-     */
-    protected function compileComment($block)
-    {
-        $out = $this->makeOutputBlock(Type::T_COMMENT);
-        $out->lines[] = $this->compileCommentValue($block, true);
-
-        $this->scope->children[] = $out;
-    }
-
-    /**
-     * Evaluate selectors
-     *
-     * @param array $selectors
-     *
-     * @return array
-     */
-    protected function evalSelectors($selectors)
-    {
-        $this->shouldEvaluate = false;
-
-        $selectors = array_map([$this, 'evalSelector'], $selectors);
-
-        // after evaluating interpolates, we might need a second pass
-        if ($this->shouldEvaluate) {
-            $selectors = $this->replaceSelfSelector($selectors, '&');
-            $buffer    = $this->collapseSelectors($selectors);
-            $parser    = $this->parserFactory(__METHOD__);
-
-            if ($parser->parseSelector($buffer, $newSelectors)) {
-                $selectors = array_map([$this, 'evalSelector'], $newSelectors);
-            }
-        }
-
-        return $selectors;
-    }
-
-    /**
-     * Evaluate selector
-     *
-     * @param array $selector
-     *
-     * @return array
-     */
-    protected function evalSelector($selector)
-    {
-        return array_map([$this, 'evalSelectorPart'], $selector);
-    }
-
-    /**
-     * Evaluate selector part; replaces all the interpolates, stripping quotes
-     *
-     * @param array $part
-     *
-     * @return array
-     */
-    protected function evalSelectorPart($part)
-    {
-        foreach ($part as &$p) {
-            if (\is_array($p) && ($p[0] === Type::T_INTERPOLATE || $p[0] === Type::T_STRING)) {
-                $p = $this->compileValue($p);
-
-                // force re-evaluation
-                if (strpos($p, '&') !== false || strpos($p, ',') !== false) {
-                    $this->shouldEvaluate = true;
-                }
-            } elseif (
-                \is_string($p) && \strlen($p) >= 2 &&
-                ($first = $p[0]) && ($first === '"' || $first === "'") &&
-                substr($p, -1) === $first
-            ) {
-                $p = substr($p, 1, -1);
-            }
-        }
-
-        return $this->flattenSelectorSingle($part);
-    }
-
-    /**
-     * Collapse selectors
-     *
-     * @param array   $selectors
-     * @param boolean $selectorFormat
-     *   if false return a collapsed string
-     *   if true return an array description of a structured selector
-     *
-     * @return string
-     */
-    protected function collapseSelectors($selectors, $selectorFormat = false)
-    {
-        $parts = [];
-
-        foreach ($selectors as $selector) {
-            $output = [];
-            $glueNext = false;
-
-            foreach ($selector as $node) {
-                $compound = '';
-
-                array_walk_recursive(
-                    $node,
-                    function ($value, $key) use (&$compound) {
-                        $compound .= $value;
-                    }
-                );
-
-                if ($selectorFormat && $this->isImmediateRelationshipCombinator($compound)) {
-                    if (\count($output)) {
-                        $output[\count($output) - 1] .= ' ' . $compound;
-                    } else {
-                        $output[] = $compound;
-                    }
-
-                    $glueNext = true;
-                } elseif ($glueNext) {
-                    $output[\count($output) - 1] .= ' ' . $compound;
-                    $glueNext = false;
-                } else {
-                    $output[] = $compound;
-                }
-            }
-
-            if ($selectorFormat) {
-                foreach ($output as &$o) {
-                    $o = [Type::T_STRING, '', [$o]];
-                }
-
-                $output = [Type::T_LIST, ' ', $output];
-            } else {
-                $output = implode(' ', $output);
-            }
-
-            $parts[] = $output;
-        }
-
-        if ($selectorFormat) {
-            $parts = [Type::T_LIST, ',', $parts];
-        } else {
-            $parts = implode(', ', $parts);
-        }
-
-        return $parts;
-    }
-
-    /**
-     * Parse down the selector and revert [self] to "&" before a reparsing
-     *
-     * @param array $selectors
-     *
-     * @return array
-     */
-    protected function replaceSelfSelector($selectors, $replace = null)
-    {
-        foreach ($selectors as &$part) {
-            if (\is_array($part)) {
-                if ($part === [Type::T_SELF]) {
-                    if (\is_null($replace)) {
-                        $replace = $this->reduce([Type::T_SELF]);
-                        $replace = $this->compileValue($replace);
-                    }
-                    $part = $replace;
-                } else {
-                    $part = $this->replaceSelfSelector($part, $replace);
-                }
-            }
-        }
-
-        return $selectors;
-    }
-
-    /**
-     * Flatten selector single; joins together .classes and #ids
-     *
-     * @param array $single
-     *
-     * @return array
-     */
-    protected function flattenSelectorSingle($single)
-    {
-        $joined = [];
-
-        foreach ($single as $part) {
-            if (
-                empty($joined) ||
-                ! \is_string($part) ||
-                preg_match('/[\[.:#%]/', $part)
-            ) {
-                $joined[] = $part;
-                continue;
-            }
-
-            if (\is_array(end($joined))) {
-                $joined[] = $part;
-            } else {
-                $joined[\count($joined) - 1] .= $part;
-            }
-        }
-
-        return $joined;
-    }
-
-    /**
-     * Compile selector to string; self(&) should have been replaced by now
-     *
-     * @param string|array $selector
-     *
-     * @return string
-     */
-    protected function compileSelector($selector)
-    {
-        if (! \is_array($selector)) {
-            return $selector; // media and the like
-        }
-
-        return implode(
-            ' ',
-            array_map(
-                [$this, 'compileSelectorPart'],
-                $selector
-            )
-        );
-    }
-
-    /**
-     * Compile selector part
-     *
-     * @param array $piece
-     *
-     * @return string
-     */
-    protected function compileSelectorPart($piece)
-    {
-        foreach ($piece as &$p) {
-            if (! \is_array($p)) {
-                continue;
-            }
-
-            switch ($p[0]) {
-                case Type::T_SELF:
-                    $p = '&';
-                    break;
-
-                default:
-                    $p = $this->compileValue($p);
-                    break;
-            }
-        }
-
-        return implode($piece);
-    }
-
-    /**
-     * Has selector placeholder?
-     *
-     * @param array $selector
-     *
-     * @return boolean
-     */
-    protected function hasSelectorPlaceholder($selector)
-    {
-        if (! \is_array($selector)) {
-            return false;
-        }
-
-        foreach ($selector as $parts) {
-            foreach ($parts as $part) {
-                if (\strlen($part) && '%' === $part[0]) {
-                    return true;
-                }
-            }
-        }
-
-        return false;
-    }
-
-    protected function pushCallStack($name = '')
-    {
-        $this->callStack[] = [
-          'n' => $name,
-          Parser::SOURCE_INDEX => $this->sourceIndex,
-          Parser::SOURCE_LINE => $this->sourceLine,
-          Parser::SOURCE_COLUMN => $this->sourceColumn
-        ];
-
-        // infinite calling loop
-        if (\count($this->callStack) > 25000) {
-            // not displayed but you can var_dump it to deep debug
-            $msg = $this->callStackMessage(true, 100);
-            $msg = 'Infinite calling loop';
-
-            throw $this->error($msg);
-        }
-    }
-
-    protected function popCallStack()
-    {
-        array_pop($this->callStack);
-    }
-
-    /**
-     * Compile children and return result
-     *
-     * @param array                                  $stms
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     * @param string                                 $traceName
-     *
-     * @return array|null
-     */
-    protected function compileChildren($stms, OutputBlock $out, $traceName = '')
-    {
-        $this->pushCallStack($traceName);
-
-        foreach ($stms as $stm) {
-            $ret = $this->compileChild($stm, $out);
-
-            if (isset($ret)) {
-                $this->popCallStack();
-
-                return $ret;
-            }
-        }
-
-        $this->popCallStack();
-
-        return null;
-    }
-
-    /**
-     * Compile children and throw exception if unexpected @return
-     *
-     * @param array                                  $stms
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     * @param \ScssPhp\ScssPhp\Block                 $selfParent
-     * @param string                                 $traceName
-     *
-     * @throws \Exception
-     */
-    protected function compileChildrenNoReturn($stms, OutputBlock $out, $selfParent = null, $traceName = '')
-    {
-        $this->pushCallStack($traceName);
-
-        foreach ($stms as $stm) {
-            if ($selfParent && isset($stm[1]) && \is_object($stm[1]) && $stm[1] instanceof Block) {
-                $stm[1]->selfParent = $selfParent;
-                $ret = $this->compileChild($stm, $out);
-                $stm[1]->selfParent = null;
-            } elseif ($selfParent && \in_array($stm[0], [TYPE::T_INCLUDE, TYPE::T_EXTEND])) {
-                $stm['selfParent'] = $selfParent;
-                $ret = $this->compileChild($stm, $out);
-                unset($stm['selfParent']);
-            } else {
-                $ret = $this->compileChild($stm, $out);
-            }
-
-            if (isset($ret)) {
-                throw $this->error('@return may only be used within a function');
-            }
-        }
-
-        $this->popCallStack();
-    }
-
-
-    /**
-     * evaluate media query : compile internal value keeping the structure inchanged
-     *
-     * @param array $queryList
-     *
-     * @return array
-     */
-    protected function evaluateMediaQuery($queryList)
-    {
-        static $parser = null;
-
-        $outQueryList = [];
-
-        foreach ($queryList as $kql => $query) {
-            $shouldReparse = false;
-
-            foreach ($query as $kq => $q) {
-                for ($i = 1; $i < \count($q); $i++) {
-                    $value = $this->compileValue($q[$i]);
-
-                    // the parser had no mean to know if media type or expression if it was an interpolation
-                    // so you need to reparse if the T_MEDIA_TYPE looks like anything else a media type
-                    if (
-                        $q[0] == Type::T_MEDIA_TYPE &&
-                        (strpos($value, '(') !== false ||
-                        strpos($value, ')') !== false ||
-                        strpos($value, ':') !== false ||
-                        strpos($value, ',') !== false)
-                    ) {
-                        $shouldReparse = true;
-                    }
-
-                    $queryList[$kql][$kq][$i] = [Type::T_KEYWORD, $value];
-                }
-            }
-
-            if ($shouldReparse) {
-                if (\is_null($parser)) {
-                    $parser = $this->parserFactory(__METHOD__);
-                }
-
-                $queryString = $this->compileMediaQuery([$queryList[$kql]]);
-                $queryString = reset($queryString);
-
-                if (strpos($queryString, '@media ') === 0) {
-                    $queryString = substr($queryString, 7);
-                    $queries = [];
-
-                    if ($parser->parseMediaQueryList($queryString, $queries)) {
-                        $queries = $this->evaluateMediaQuery($queries[2]);
-
-                        while (\count($queries)) {
-                            $outQueryList[] = array_shift($queries);
-                        }
-
-                        continue;
-                    }
-                }
-            }
-
-            $outQueryList[] = $queryList[$kql];
-        }
-
-        return $outQueryList;
-    }
-
-    /**
-     * Compile media query
-     *
-     * @param array $queryList
-     *
-     * @return array
-     */
-    protected function compileMediaQuery($queryList)
-    {
-        $start   = '@media ';
-        $default = trim($start);
-        $out     = [];
-        $current = '';
-
-        foreach ($queryList as $query) {
-            $type = null;
-            $parts = [];
-
-            $mediaTypeOnly = true;
-
-            foreach ($query as $q) {
-                if ($q[0] !== Type::T_MEDIA_TYPE) {
-                    $mediaTypeOnly = false;
-                    break;
-                }
-            }
-
-            foreach ($query as $q) {
-                switch ($q[0]) {
-                    case Type::T_MEDIA_TYPE:
-                        $newType = array_map([$this, 'compileValue'], \array_slice($q, 1));
-
-                        // combining not and anything else than media type is too risky and should be avoided
-                        if (! $mediaTypeOnly) {
-                            if (\in_array(Type::T_NOT, $newType) || ($type && \in_array(Type::T_NOT, $type) )) {
-                                if ($type) {
-                                    array_unshift($parts, implode(' ', array_filter($type)));
-                                }
-
-                                if (! empty($parts)) {
-                                    if (\strlen($current)) {
-                                        $current .= $this->formatter->tagSeparator;
-                                    }
-
-                                    $current .= implode(' and ', $parts);
-                                }
-
-                                if ($current) {
-                                    $out[] = $start . $current;
-                                }
-
-                                $current = '';
-                                $type    = null;
-                                $parts   = [];
-                            }
-                        }
-
-                        if ($newType === ['all'] && $default) {
-                            $default = $start . 'all';
-                        }
-
-                        // all can be safely ignored and mixed with whatever else
-                        if ($newType !== ['all']) {
-                            if ($type) {
-                                $type = $this->mergeMediaTypes($type, $newType);
-
-                                if (empty($type)) {
-                                    // merge failed : ignore this query that is not valid, skip to the next one
-                                    $parts = [];
-                                    $default = ''; // if everything fail, no @media at all
-                                    continue 3;
-                                }
-                            } else {
-                                $type = $newType;
-                            }
-                        }
-                        break;
-
-                    case Type::T_MEDIA_EXPRESSION:
-                        if (isset($q[2])) {
-                            $parts[] = '('
-                                . $this->compileValue($q[1])
-                                . $this->formatter->assignSeparator
-                                . $this->compileValue($q[2])
-                                . ')';
-                        } else {
-                            $parts[] = '('
-                                . $this->compileValue($q[1])
-                                . ')';
-                        }
-                        break;
-
-                    case Type::T_MEDIA_VALUE:
-                        $parts[] = $this->compileValue($q[1]);
-                        break;
-                }
-            }
-
-            if ($type) {
-                array_unshift($parts, implode(' ', array_filter($type)));
-            }
-
-            if (! empty($parts)) {
-                if (\strlen($current)) {
-                    $current .= $this->formatter->tagSeparator;
-                }
-
-                $current .= implode(' and ', $parts);
-            }
-        }
-
-        if ($current) {
-            $out[] = $start . $current;
-        }
-
-        // no @media type except all, and no conflict?
-        if (! $out && $default) {
-            $out[] = $default;
-        }
-
-        return $out;
-    }
-
-    /**
-     * Merge direct relationships between selectors
-     *
-     * @param array $selectors1
-     * @param array $selectors2
-     *
-     * @return array
-     */
-    protected function mergeDirectRelationships($selectors1, $selectors2)
-    {
-        if (empty($selectors1) || empty($selectors2)) {
-            return array_merge($selectors1, $selectors2);
-        }
-
-        $part1 = end($selectors1);
-        $part2 = end($selectors2);
-
-        if (! $this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
-            return array_merge($selectors1, $selectors2);
-        }
-
-        $merged = [];
-
-        do {
-            $part1 = array_pop($selectors1);
-            $part2 = array_pop($selectors2);
-
-            if (! $this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
-                if ($this->isImmediateRelationshipCombinator(reset($merged)[0])) {
-                    array_unshift($merged, [$part1[0] . $part2[0]]);
-                    $merged = array_merge($selectors1, $selectors2, $merged);
-                } else {
-                    $merged = array_merge($selectors1, [$part1], $selectors2, [$part2], $merged);
-                }
-
-                break;
-            }
-
-            array_unshift($merged, $part1);
-        } while (! empty($selectors1) && ! empty($selectors2));
-
-        return $merged;
-    }
-
-    /**
-     * Merge media types
-     *
-     * @param array $type1
-     * @param array $type2
-     *
-     * @return array|null
-     */
-    protected function mergeMediaTypes($type1, $type2)
-    {
-        if (empty($type1)) {
-            return $type2;
-        }
-
-        if (empty($type2)) {
-            return $type1;
-        }
-
-        if (\count($type1) > 1) {
-            $m1 = strtolower($type1[0]);
-            $t1 = strtolower($type1[1]);
-        } else {
-            $m1 = '';
-            $t1 = strtolower($type1[0]);
-        }
-
-        if (\count($type2) > 1) {
-            $m2 = strtolower($type2[0]);
-            $t2 = strtolower($type2[1]);
-        } else {
-            $m2 = '';
-            $t2 = strtolower($type2[0]);
-        }
-
-        if (($m1 === Type::T_NOT) ^ ($m2 === Type::T_NOT)) {
-            if ($t1 === $t2) {
-                return null;
-            }
-
-            return [
-                $m1 === Type::T_NOT ? $m2 : $m1,
-                $m1 === Type::T_NOT ? $t2 : $t1,
-            ];
-        }
-
-        if ($m1 === Type::T_NOT && $m2 === Type::T_NOT) {
-            // CSS has no way of representing "neither screen nor print"
-            if ($t1 !== $t2) {
-                return null;
-            }
-
-            return [Type::T_NOT, $t1];
-        }
-
-        if ($t1 !== $t2) {
-            return null;
-        }
-
-        // t1 == t2, neither m1 nor m2 are "not"
-        return [empty($m1) ? $m2 : $m1, $t1];
-    }
-
-    /**
-     * Compile import; returns true if the value was something that could be imported
-     *
-     * @param array                                  $rawPath
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     * @param boolean                                $once
-     *
-     * @return boolean
-     */
-    protected function compileImport($rawPath, OutputBlock $out, $once = false)
-    {
-        if ($rawPath[0] === Type::T_STRING) {
-            $path = $this->compileStringContent($rawPath);
-
-            if (strpos($path, 'url(') !== 0 && $path = $this->findImport($path)) {
-                if (! $once || ! \in_array($path, $this->importedFiles)) {
-                    $this->importFile($path, $out);
-                    $this->importedFiles[] = $path;
-                }
-
-                return true;
-            }
-
-            $this->appendRootDirective('@import ' . $this->compileImportPath($rawPath) . ';', $out);
-
-            return false;
-        }
-
-        if ($rawPath[0] === Type::T_LIST) {
-            // handle a list of strings
-            if (\count($rawPath[2]) === 0) {
-                return false;
-            }
-
-            foreach ($rawPath[2] as $path) {
-                if ($path[0] !== Type::T_STRING) {
-                    $this->appendRootDirective('@import ' . $this->compileImportPath($rawPath) . ';', $out);
-
-                    return false;
-                }
-            }
-
-            foreach ($rawPath[2] as $path) {
-                $this->compileImport($path, $out, $once);
-            }
-
-            return true;
-        }
-
-        $this->appendRootDirective('@import ' . $this->compileImportPath($rawPath) . ';', $out);
-
-        return false;
-    }
-
-    /**
-     * @param $rawPath
-     * @return string
-     * @throws CompilerException
-     */
-    protected function compileImportPath($rawPath)
-    {
-        $path = $this->compileValue($rawPath);
-
-        // case url() without quotes : supress \r \n remaining in the path
-        // if this is a real string there can not be CR or LF char
-        if (strpos($path, 'url(') === 0) {
-            $path = str_replace(array("\r", "\n"), array('', ' '), $path);
-        } else {
-            // if this is a file name in a string, spaces shoudl be escaped
-            $path = $this->reduce($rawPath);
-            $path = $this->escapeImportPathString($path);
-            $path = $this->compileValue($path);
-        }
-
-        return $path;
-    }
-
-    /**
-     * @param array $path
-     * @return array
-     * @throws CompilerException
-     */
-    protected function escapeImportPathString($path)
-    {
-        switch ($path[0]) {
-            case Type::T_LIST:
-                foreach ($path[2] as $k => $v) {
-                    $path[2][$k] = $this->escapeImportPathString($v);
-                }
-                break;
-            case Type::T_STRING:
-                if ($path[1]) {
-                    $path = $this->compileValue($path);
-                    $path = str_replace(' ', '\\ ', $path);
-                    $path = [Type::T_KEYWORD, $path];
-                }
-                break;
-        }
-
-        return $path;
-    }
-
-    /**
-     * Append a root directive like @import or @charset as near as the possible from the source code
-     * (keeping before comments, @import and @charset coming before in the source code)
-     *
-     * @param string                                        $line
-     * @param @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     * @param array                                         $allowed
-     */
-    protected function appendRootDirective($line, $out, $allowed = [Type::T_COMMENT])
-    {
-        $root = $out;
-
-        while ($root->parent) {
-            $root = $root->parent;
-        }
-
-        $i = 0;
-
-        while ($i < \count($root->children)) {
-            if (! isset($root->children[$i]->type) || ! \in_array($root->children[$i]->type, $allowed)) {
-                break;
-            }
-
-            $i++;
-        }
-
-        // remove incompatible children from the bottom of the list
-        $saveChildren = [];
-
-        while ($i < \count($root->children)) {
-            $saveChildren[] = array_pop($root->children);
-        }
-
-        // insert the directive as a comment
-        $child = $this->makeOutputBlock(Type::T_COMMENT);
-        $child->lines[]      = $line;
-        $child->sourceName   = $this->sourceNames[$this->sourceIndex];
-        $child->sourceLine   = $this->sourceLine;
-        $child->sourceColumn = $this->sourceColumn;
-
-        $root->children[] = $child;
-
-        // repush children
-        while (\count($saveChildren)) {
-            $root->children[] = array_pop($saveChildren);
-        }
-    }
-
-    /**
-     * Append lines to the current output block:
-     * directly to the block or through a child if necessary
-     *
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     * @param string                                 $type
-     * @param string|mixed                           $line
-     */
-    protected function appendOutputLine(OutputBlock $out, $type, $line)
-    {
-        $outWrite = &$out;
-
-        // check if it's a flat output or not
-        if (\count($out->children)) {
-            $lastChild = &$out->children[\count($out->children) - 1];
-
-            if (
-                $lastChild->depth === $out->depth &&
-                \is_null($lastChild->selectors) &&
-                ! \count($lastChild->children)
-            ) {
-                $outWrite = $lastChild;
-            } else {
-                $nextLines = $this->makeOutputBlock($type);
-                $nextLines->parent = $out;
-                $nextLines->depth  = $out->depth;
-
-                $out->children[] = $nextLines;
-                $outWrite = &$nextLines;
-            }
-        }
-
-        $outWrite->lines[] = $line;
-    }
-
-    /**
-     * Compile child; returns a value to halt execution
-     *
-     * @param array                                  $child
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     *
-     * @return array
-     */
-    protected function compileChild($child, OutputBlock $out)
-    {
-        if (isset($child[Parser::SOURCE_LINE])) {
-            $this->sourceIndex  = isset($child[Parser::SOURCE_INDEX]) ? $child[Parser::SOURCE_INDEX] : null;
-            $this->sourceLine   = isset($child[Parser::SOURCE_LINE]) ? $child[Parser::SOURCE_LINE] : -1;
-            $this->sourceColumn = isset($child[Parser::SOURCE_COLUMN]) ? $child[Parser::SOURCE_COLUMN] : -1;
-        } elseif (\is_array($child) && isset($child[1]->sourceLine)) {
-            $this->sourceIndex  = $child[1]->sourceIndex;
-            $this->sourceLine   = $child[1]->sourceLine;
-            $this->sourceColumn = $child[1]->sourceColumn;
-        } elseif (! empty($out->sourceLine) && ! empty($out->sourceName)) {
-            $this->sourceLine   = $out->sourceLine;
-            $this->sourceIndex  = array_search($out->sourceName, $this->sourceNames);
-            $this->sourceColumn = $out->sourceColumn;
-
-            if ($this->sourceIndex === false) {
-                $this->sourceIndex = null;
-            }
-        }
-
-        switch ($child[0]) {
-            case Type::T_SCSSPHP_IMPORT_ONCE:
-                $rawPath = $this->reduce($child[1]);
-
-                $this->compileImport($rawPath, $out, true);
-                break;
-
-            case Type::T_IMPORT:
-                $rawPath = $this->reduce($child[1]);
-
-                $this->compileImport($rawPath, $out);
-                break;
-
-            case Type::T_DIRECTIVE:
-                $this->compileDirective($child[1], $out);
-                break;
-
-            case Type::T_AT_ROOT:
-                $this->compileAtRoot($child[1]);
-                break;
-
-            case Type::T_MEDIA:
-                $this->compileMedia($child[1]);
-                break;
-
-            case Type::T_BLOCK:
-                $this->compileBlock($child[1]);
-                break;
-
-            case Type::T_CHARSET:
-                if (! $this->charsetSeen) {
-                    $this->charsetSeen = true;
-                    $this->appendRootDirective('@charset ' . $this->compileValue($child[1]) . ';', $out);
-                }
-                break;
-
-            case Type::T_CUSTOM_PROPERTY:
-                list(, $name, $value) = $child;
-                $compiledName = $this->compileValue($name);
-
-                // if the value reduces to null from something else then
-                // the property should be discarded
-                if ($value[0] !== Type::T_NULL) {
-                    $value = $this->reduce($value);
-
-                    if ($value[0] === Type::T_NULL || $value === static::$nullString) {
-                        break;
-                    }
-                }
-
-                $compiledValue = $this->compileValue($value);
-
-                $line = $this->formatter->customProperty(
-                    $compiledName,
-                    $compiledValue
-                );
-
-                $this->appendOutputLine($out, Type::T_ASSIGN, $line);
-                break;
-
-            case Type::T_ASSIGN:
-                list(, $name, $value) = $child;
-
-                if ($name[0] === Type::T_VARIABLE) {
-                    $flags     = isset($child[3]) ? $child[3] : [];
-                    $isDefault = \in_array('!default', $flags);
-                    $isGlobal  = \in_array('!global', $flags);
-
-                    if ($isGlobal) {
-                        $this->set($name[1], $this->reduce($value), false, $this->rootEnv, $value);
-                        break;
-                    }
-
-                    $shouldSet = $isDefault &&
-                        (\is_null($result = $this->get($name[1], false)) ||
-                        $result === static::$null);
-
-                    if (! $isDefault || $shouldSet) {
-                        $this->set($name[1], $this->reduce($value), true, null, $value);
-                    }
-                    break;
-                }
-
-                $compiledName = $this->compileValue($name);
-
-                // handle shorthand syntaxes : size / line-height...
-                if (\in_array($compiledName, ['font', 'grid-row', 'grid-column', 'border-radius'])) {
-                    if ($value[0] === Type::T_VARIABLE) {
-                        // if the font value comes from variable, the content is already reduced
-                        // (i.e., formulas were already calculated), so we need the original unreduced value
-                        $value = $this->get($value[1], true, null, true);
-                    }
-
-                    $shorthandValue=&$value;
-
-                    $shorthandDividerNeedsUnit = false;
-                    $maxListElements           = null;
-                    $maxShorthandDividers      = 1;
-
-                    switch ($compiledName) {
-                        case 'border-radius':
-                            $maxListElements = 4;
-                            $shorthandDividerNeedsUnit = true;
-                            break;
-                    }
-
-                    if ($compiledName === 'font' && $value[0] === Type::T_LIST && $value[1] === ',') {
-                        // this is the case if more than one font is given: example: "font: 400 1em/1.3 arial,helvetica"
-                        // we need to handle the first list element
-                        $shorthandValue=&$value[2][0];
-                    }
-
-                    if ($shorthandValue[0] === Type::T_EXPRESSION && $shorthandValue[1] === '/') {
-                        $revert = true;
-
-                        if ($shorthandDividerNeedsUnit) {
-                            $divider = $shorthandValue[3];
-
-                            if (\is_array($divider)) {
-                                $divider = $this->reduce($divider, true);
-                            }
-
-                            if (\intval($divider->dimension) && ! \count($divider->units)) {
-                                $revert = false;
-                            }
-                        }
-
-                        if ($revert) {
-                            $shorthandValue = $this->expToString($shorthandValue);
-                        }
-                    } elseif ($shorthandValue[0] === Type::T_LIST) {
-                        foreach ($shorthandValue[2] as &$item) {
-                            if ($item[0] === Type::T_EXPRESSION && $item[1] === '/') {
-                                if ($maxShorthandDividers > 0) {
-                                    $revert = true;
-
-                                    // if the list of values is too long, this has to be a shorthand,
-                                    // otherwise it could be a real division
-                                    if (\is_null($maxListElements) || \count($shorthandValue[2]) <= $maxListElements) {
-                                        if ($shorthandDividerNeedsUnit) {
-                                            $divider = $item[3];
-
-                                            if (\is_array($divider)) {
-                                                $divider = $this->reduce($divider, true);
-                                            }
-
-                                            if (\intval($divider->dimension) && ! \count($divider->units)) {
-                                                $revert = false;
-                                            }
-                                        }
-                                    }
-
-                                    if ($revert) {
-                                        $item = $this->expToString($item);
-                                        $maxShorthandDividers--;
-                                    }
-                                }
-                            }
-                        }
-                    }
-                }
-
-                // if the value reduces to null from something else then
-                // the property should be discarded
-                if ($value[0] !== Type::T_NULL) {
-                    $value = $this->reduce($value);
-
-                    if ($value[0] === Type::T_NULL || $value === static::$nullString) {
-                        break;
-                    }
-                }
-
-                $compiledValue = $this->compileValue($value);
-
-                // ignore empty value
-                if (\strlen($compiledValue)) {
-                    $line = $this->formatter->property(
-                        $compiledName,
-                        $compiledValue
-                    );
-                    $this->appendOutputLine($out, Type::T_ASSIGN, $line);
-                }
-                break;
-
-            case Type::T_COMMENT:
-                if ($out->type === Type::T_ROOT) {
-                    $this->compileComment($child);
-                    break;
-                }
-
-                $line = $this->compileCommentValue($child, true);
-                $this->appendOutputLine($out, Type::T_COMMENT, $line);
-                break;
-
-            case Type::T_MIXIN:
-            case Type::T_FUNCTION:
-                list(, $block) = $child;
-                // the block need to be able to go up to it's parent env to resolve vars
-                $block->parentEnv = $this->getStoreEnv();
-                $this->set(static::$namespaces[$block->type] . $block->name, $block, true);
-                break;
-
-            case Type::T_EXTEND:
-                foreach ($child[1] as $sel) {
-                    $sel = $this->replaceSelfSelector($sel);
-                    $results = $this->evalSelectors([$sel]);
-
-                    foreach ($results as $result) {
-                        // only use the first one
-                        $result = current($result);
-                        $selectors = $out->selectors;
-
-                        if (! $selectors && isset($child['selfParent'])) {
-                            $selectors = $this->multiplySelectors($this->env, $child['selfParent']);
-                        }
-
-                        $this->pushExtends($result, $selectors, $child);
-                    }
-                }
-                break;
-
-            case Type::T_IF:
-                list(, $if) = $child;
-
-                if ($this->isTruthy($this->reduce($if->cond, true))) {
-                    return $this->compileChildren($if->children, $out);
-                }
-
-                foreach ($if->cases as $case) {
-                    if (
-                        $case->type === Type::T_ELSE ||
-                        $case->type === Type::T_ELSEIF && $this->isTruthy($this->reduce($case->cond))
-                    ) {
-                        return $this->compileChildren($case->children, $out);
-                    }
-                }
-                break;
-
-            case Type::T_EACH:
-                list(, $each) = $child;
-
-                $list = $this->coerceList($this->reduce($each->list), ',', true);
-
-                $this->pushEnv();
-
-                foreach ($list[2] as $item) {
-                    if (\count($each->vars) === 1) {
-                        $this->set($each->vars[0], $item, true);
-                    } else {
-                        list(,, $values) = $this->coerceList($item);
-
-                        foreach ($each->vars as $i => $var) {
-                            $this->set($var, isset($values[$i]) ? $values[$i] : static::$null, true);
-                        }
-                    }
-
-                    $ret = $this->compileChildren($each->children, $out);
-
-                    if ($ret) {
-                        if ($ret[0] !== Type::T_CONTROL) {
-                            $store = $this->env->store;
-                            $this->popEnv();
-                            $this->backPropagateEnv($store, $each->vars);
-
-                            return $ret;
-                        }
-
-                        if ($ret[1]) {
-                            break;
-                        }
-                    }
-                }
-                $store = $this->env->store;
-                $this->popEnv();
-                $this->backPropagateEnv($store, $each->vars);
-
-                break;
-
-            case Type::T_WHILE:
-                list(, $while) = $child;
-
-                while ($this->isTruthy($this->reduce($while->cond, true))) {
-                    $ret = $this->compileChildren($while->children, $out);
-
-                    if ($ret) {
-                        if ($ret[0] !== Type::T_CONTROL) {
-                            return $ret;
-                        }
+	const LINE_COMMENTS = 1;
+	const DEBUG_INFO    = 2;
+
+	const WITH_RULE     = 1;
+	const WITH_MEDIA    = 2;
+	const WITH_SUPPORTS = 4;
+	const WITH_ALL      = 7;
+
+	const SOURCE_MAP_NONE   = 0;
+	const SOURCE_MAP_INLINE = 1;
+	const SOURCE_MAP_FILE   = 2;
+
+	/**
+	 * @var array
+	 */
+	protected static $operatorNames = [
+		'+'   => 'add',
+		'-'   => 'sub',
+		'*'   => 'mul',
+		'/'   => 'div',
+		'%'   => 'mod',
+
+		'=='  => 'eq',
+		'!='  => 'neq',
+		'<'   => 'lt',
+		'>'   => 'gt',
+
+		'<='  => 'lte',
+		'>='  => 'gte',
+		'<=>' => 'cmp',
+	];
+
+	/**
+	 * @var array
+	 */
+	protected static $namespaces = [
+		'special'  => '%',
+		'mixin'    => '@',
+		'function' => '^',
+	];
+
+	public static $true         = [Type::T_KEYWORD, 'true'];
+	public static $false        = [Type::T_KEYWORD, 'false'];
+	public static $NaN          = [Type::T_KEYWORD, 'NaN'];
+	public static $Infinity     = [Type::T_KEYWORD, 'Infinity'];
+	public static $null         = [Type::T_NULL];
+	public static $nullString   = [Type::T_STRING, '', []];
+	public static $defaultValue = [Type::T_KEYWORD, ''];
+	public static $selfSelector = [Type::T_SELF];
+	public static $emptyList    = [Type::T_LIST, '', []];
+	public static $emptyMap     = [Type::T_MAP, [], []];
+	public static $emptyString  = [Type::T_STRING, '"', []];
+	public static $with         = [Type::T_KEYWORD, 'with'];
+	public static $without      = [Type::T_KEYWORD, 'without'];
+
+	protected $importPaths = [''];
+	protected $importCache = [];
+	protected $importedFiles = [];
+	protected $userFunctions = [];
+	protected $registeredVars = [];
+	protected $registeredFeatures = [
+		'extend-selector-pseudoclass' => false,
+		'at-error'                    => true,
+		'units-level-3'               => false,
+		'global-variable-shadowing'   => false,
+	];
+
+	protected $encoding = null;
+	protected $lineNumberStyle = null;
+
+	protected $sourceMap = self::SOURCE_MAP_NONE;
+	protected $sourceMapOptions = [];
+
+	/**
+	 * @var string|\ScssPhp\ScssPhp\Formatter
+	 */
+	protected $formatter = 'ScssPhp\ScssPhp\Formatter\Nested';
+
+	protected $rootEnv;
+	protected $rootBlock;
+
+	/**
+	 * @var \ScssPhp\ScssPhp\Compiler\Environment
+	 */
+	protected $env;
+	protected $scope;
+	protected $storeEnv;
+	protected $charsetSeen;
+	protected $sourceNames;
+
+	protected $cache;
+
+	protected $indentLevel;
+	protected $extends;
+	protected $extendsMap;
+	protected $parsedFiles;
+	protected $parser;
+	protected $sourceIndex;
+	protected $sourceLine;
+	protected $sourceColumn;
+	protected $stderr;
+	protected $shouldEvaluate;
+	protected $ignoreErrors;
+	protected $ignoreCallStackMessage = false;
+
+	protected $callStack = [];
+
+	/**
+	 * Constructor
+	 *
+	 * @param array|null $cacheOptions
+	 */
+	public function __construct($cacheOptions = null)
+	{
+		$this->parsedFiles = [];
+		$this->sourceNames = [];
+
+		if ($cacheOptions) {
+			$this->cache = new Cache($cacheOptions);
+		}
+
+		$this->stderr = fopen('php://stderr', 'w');
+	}
+
+	/**
+	 * Get compiler options
+	 *
+	 * @return array
+	 */
+	public function getCompileOptions()
+	{
+		$options = [
+			'importPaths'        => $this->importPaths,
+			'registeredVars'     => $this->registeredVars,
+			'registeredFeatures' => $this->registeredFeatures,
+			'encoding'           => $this->encoding,
+			'sourceMap'          => serialize($this->sourceMap),
+			'sourceMapOptions'   => $this->sourceMapOptions,
+			'formatter'          => $this->formatter,
+		];
+
+		return $options;
+	}
+
+	/**
+	 * Set an alternative error output stream, for testing purpose only
+	 *
+	 * @param resource $handle
+	 */
+	public function setErrorOuput($handle)
+	{
+		$this->stderr = $handle;
+	}
+
+	/**
+	 * Compile scss
+	 *
+	 * @api
+	 *
+	 * @param string $code
+	 * @param string $path
+	 *
+	 * @return string
+	 */
+	public function compile($code, $path = null)
+	{
+		if ($this->cache) {
+			$cacheKey       = ($path ? $path : '(stdin)') . ':' . md5($code);
+			$compileOptions = $this->getCompileOptions();
+			$cache          = $this->cache->getCache('compile', $cacheKey, $compileOptions);
+
+			if (\is_array($cache) && isset($cache['dependencies']) && isset($cache['out'])) {
+				// check if any dependency file changed before accepting the cache
+				foreach ($cache['dependencies'] as $file => $mtime) {
+					if (! is_file($file) || filemtime($file) !== $mtime) {
+						unset($cache);
+						break;
+					}
+				}
+
+				if (isset($cache)) {
+					return $cache['out'];
+				}
+			}
+		}
+
+
+		$this->indentLevel    = -1;
+		$this->extends        = [];
+		$this->extendsMap     = [];
+		$this->sourceIndex    = null;
+		$this->sourceLine     = null;
+		$this->sourceColumn   = null;
+		$this->env            = null;
+		$this->scope          = null;
+		$this->storeEnv       = null;
+		$this->charsetSeen    = null;
+		$this->shouldEvaluate = null;
+		$this->ignoreCallStackMessage = false;
+
+		$this->parser = $this->parserFactory($path);
+		$tree         = $this->parser->parse($code);
+		$this->parser = null;
+
+		$this->formatter = new $this->formatter();
+		$this->rootBlock = null;
+		$this->rootEnv   = $this->pushEnv($tree);
+
+		$this->injectVariables($this->registeredVars);
+		$this->compileRoot($tree);
+		$this->popEnv();
+
+		$sourceMapGenerator = null;
+
+		if ($this->sourceMap) {
+			if (\is_object($this->sourceMap) && $this->sourceMap instanceof SourceMapGenerator) {
+				$sourceMapGenerator = $this->sourceMap;
+				$this->sourceMap = self::SOURCE_MAP_FILE;
+			} elseif ($this->sourceMap !== self::SOURCE_MAP_NONE) {
+				$sourceMapGenerator = new SourceMapGenerator($this->sourceMapOptions);
+			}
+		}
+
+		$out = $this->formatter->format($this->scope, $sourceMapGenerator);
+
+		if (! empty($out) && $this->sourceMap && $this->sourceMap !== self::SOURCE_MAP_NONE) {
+			$sourceMap    = $sourceMapGenerator->generateJson();
+			$sourceMapUrl = null;
+
+			switch ($this->sourceMap) {
+				case self::SOURCE_MAP_INLINE:
+					$sourceMapUrl = sprintf('data:application/json,%s', Util::encodeURIComponent($sourceMap));
+					break;
+
+				case self::SOURCE_MAP_FILE:
+					$sourceMapUrl = $sourceMapGenerator->saveMap($sourceMap);
+					break;
+			}
+
+			$out .= sprintf('/*# sourceMappingURL=%s */', $sourceMapUrl);
+		}
+
+		if ($this->cache && isset($cacheKey) && isset($compileOptions)) {
+			$v = [
+				'dependencies' => $this->getParsedFiles(),
+				'out' => &$out,
+			];
+
+			$this->cache->setCache('compile', $cacheKey, $v, $compileOptions);
+		}
+
+		return $out;
+	}
+
+	/**
+	 * Instantiate parser
+	 *
+	 * @param string $path
+	 *
+	 * @return \ScssPhp\ScssPhp\Parser
+	 */
+	protected function parserFactory($path)
+	{
+		// https://sass-lang.com/documentation/at-rules/import
+		// CSS files imported by Sass don’t allow any special Sass features.
+		// In order to make sure authors don’t accidentally write Sass in their CSS,
+		// all Sass features that aren’t also valid CSS will produce errors.
+		// Otherwise, the CSS will be rendered as-is. It can even be extended!
+		$cssOnly = false;
+
+		if (substr($path, '-4') === '.css') {
+			$cssOnly = true;
+		}
+
+		$parser = new Parser($path, \count($this->sourceNames), $this->encoding, $this->cache, $cssOnly);
+
+		$this->sourceNames[] = $path;
+		$this->addParsedFile($path);
+
+		return $parser;
+	}
+
+	/**
+	 * Is self extend?
+	 *
+	 * @param array $target
+	 * @param array $origin
+	 *
+	 * @return boolean
+	 */
+	protected function isSelfExtend($target, $origin)
+	{
+		foreach ($origin as $sel) {
+			if (\in_array($target, $sel)) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Push extends
+	 *
+	 * @param array      $target
+	 * @param array      $origin
+	 * @param array|null $block
+	 */
+	protected function pushExtends($target, $origin, $block)
+	{
+		$i = \count($this->extends);
+		$this->extends[] = [$target, $origin, $block];
+
+		foreach ($target as $part) {
+			if (isset($this->extendsMap[$part])) {
+				$this->extendsMap[$part][] = $i;
+			} else {
+				$this->extendsMap[$part] = [$i];
+			}
+		}
+	}
+
+	/**
+	 * Make output block
+	 *
+	 * @param string $type
+	 * @param array  $selectors
+	 *
+	 * @return \ScssPhp\ScssPhp\Formatter\OutputBlock
+	 */
+	protected function makeOutputBlock($type, $selectors = null)
+	{
+		$out = new OutputBlock();
+		$out->type      = $type;
+		$out->lines     = [];
+		$out->children  = [];
+		$out->parent    = $this->scope;
+		$out->selectors = $selectors;
+		$out->depth     = $this->env->depth;
+
+		if ($this->env->block instanceof Block) {
+			$out->sourceName   = $this->env->block->sourceName;
+			$out->sourceLine   = $this->env->block->sourceLine;
+			$out->sourceColumn = $this->env->block->sourceColumn;
+		} else {
+			$out->sourceName   = null;
+			$out->sourceLine   = null;
+			$out->sourceColumn = null;
+		}
+
+		return $out;
+	}
+
+	/**
+	 * Compile root
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $rootBlock
+	 */
+	protected function compileRoot(Block $rootBlock)
+	{
+		$this->rootBlock = $this->scope = $this->makeOutputBlock(Type::T_ROOT);
+
+		$this->compileChildrenNoReturn($rootBlock->children, $this->scope);
+		$this->flattenSelectors($this->scope);
+		$this->missingSelectors();
+	}
+
+	/**
+	 * Report missing selectors
+	 */
+	protected function missingSelectors()
+	{
+		foreach ($this->extends as $extend) {
+			if (isset($extend[3])) {
+				continue;
+			}
+
+			list($target, $origin, $block) = $extend;
+
+			// ignore if !optional
+			if ($block[2]) {
+				continue;
+			}
+
+			$target = implode(' ', $target);
+			$origin = $this->collapseSelectors($origin);
+
+			$this->sourceLine = $block[Parser::SOURCE_LINE];
+			throw $this->error("\"$origin\" failed to @extend \"$target\". The selector \"$target\" was not found.");
+		}
+	}
+
+	/**
+	 * Flatten selectors
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $block
+	 * @param string                                 $parentKey
+	 */
+	protected function flattenSelectors(OutputBlock $block, $parentKey = null)
+	{
+		if ($block->selectors) {
+			$selectors = [];
+
+			foreach ($block->selectors as $s) {
+				$selectors[] = $s;
+
+				if (! \is_array($s)) {
+					continue;
+				}
+
+				// check extends
+				if (! empty($this->extendsMap)) {
+					$this->matchExtends($s, $selectors);
+
+					// remove duplicates
+					array_walk($selectors, function (&$value) {
+						$value = serialize($value);
+					});
+
+					$selectors = array_unique($selectors);
+
+					array_walk($selectors, function (&$value) {
+						$value = unserialize($value);
+					});
+				}
+			}
+
+			$block->selectors = [];
+			$placeholderSelector = false;
+
+			foreach ($selectors as $selector) {
+				if ($this->hasSelectorPlaceholder($selector)) {
+					$placeholderSelector = true;
+					continue;
+				}
+
+				$block->selectors[] = $this->compileSelector($selector);
+			}
+
+			if ($placeholderSelector && 0 === \count($block->selectors) && null !== $parentKey) {
+				unset($block->parent->children[$parentKey]);
+
+				return;
+			}
+		}
+
+		foreach ($block->children as $key => $child) {
+			$this->flattenSelectors($child, $key);
+		}
+	}
+
+	/**
+	 * Glue parts of :not( or :nth-child( ... that are in general splitted in selectors parts
+	 *
+	 * @param array $parts
+	 *
+	 * @return array
+	 */
+	protected function glueFunctionSelectors($parts)
+	{
+		$new = [];
+
+		foreach ($parts as $part) {
+			if (\is_array($part)) {
+				$part = $this->glueFunctionSelectors($part);
+				$new[] = $part;
+			} else {
+				// a selector part finishing with a ) is the last part of a :not( or :nth-child(
+				// and need to be joined to this
+				if (
+					\count($new) && \is_string($new[\count($new) - 1]) &&
+					\strlen($part) && substr($part, -1) === ')' && strpos($part, '(') === false
+				) {
+					while (\count($new) > 1 && substr($new[\count($new) - 1], -1) !== '(') {
+						$part = array_pop($new) . $part;
+					}
+					$new[\count($new) - 1] .= $part;
+				} else {
+					$new[] = $part;
+				}
+			}
+		}
+
+		return $new;
+	}
+
+	/**
+	 * Match extends
+	 *
+	 * @param array   $selector
+	 * @param array   $out
+	 * @param integer $from
+	 * @param boolean $initial
+	 */
+	protected function matchExtends($selector, &$out, $from = 0, $initial = true)
+	{
+		static $partsPile = [];
+		$selector = $this->glueFunctionSelectors($selector);
+
+		if (\count($selector) == 1 && \in_array(reset($selector), $partsPile)) {
+			return;
+		}
+
+		$outRecurs = [];
+
+		foreach ($selector as $i => $part) {
+			if ($i < $from) {
+				continue;
+			}
+
+			// check that we are not building an infinite loop of extensions
+			// if the new part is just including a previous part don't try to extend anymore
+			if (\count($part) > 1) {
+				foreach ($partsPile as $previousPart) {
+					if (! \count(array_diff($previousPart, $part))) {
+						continue 2;
+					}
+				}
+			}
+
+			$partsPile[] = $part;
+
+			if ($this->matchExtendsSingle($part, $origin, $initial)) {
+				$after       = \array_slice($selector, $i + 1);
+				$before      = \array_slice($selector, 0, $i);
+				list($before, $nonBreakableBefore) = $this->extractRelationshipFromFragment($before);
+
+				foreach ($origin as $new) {
+					$k = 0;
+
+					// remove shared parts
+					if (\count($new) > 1) {
+						while ($k < $i && isset($new[$k]) && $selector[$k] === $new[$k]) {
+							$k++;
+						}
+					}
+
+					if (\count($nonBreakableBefore) && $k === \count($new)) {
+						$k--;
+					}
+
+					$replacement = [];
+					$tempReplacement = $k > 0 ? \array_slice($new, $k) : $new;
+
+					for ($l = \count($tempReplacement) - 1; $l >= 0; $l--) {
+						$slice = [];
+
+						foreach ($tempReplacement[$l] as $chunk) {
+							if (! \in_array($chunk, $slice)) {
+								$slice[] = $chunk;
+							}
+						}
+
+						array_unshift($replacement, $slice);
+
+						if (! $this->isImmediateRelationshipCombinator(end($slice))) {
+							break;
+						}
+					}
+
+					$afterBefore = $l != 0 ? \array_slice($tempReplacement, 0, $l) : [];
+
+					// Merge shared direct relationships.
+					$mergedBefore = $this->mergeDirectRelationships($afterBefore, $nonBreakableBefore);
+
+					$result = array_merge(
+						$before,
+						$mergedBefore,
+						$replacement,
+						$after
+					);
+
+					if ($result === $selector) {
+						continue;
+					}
+
+					$this->pushOrMergeExtentedSelector($out, $result);
+
+					// recursively check for more matches
+					$startRecurseFrom = \count($before) + min(\count($nonBreakableBefore), \count($mergedBefore));
+
+					if (\count($origin) > 1) {
+						$this->matchExtends($result, $out, $startRecurseFrom, false);
+					} else {
+						$this->matchExtends($result, $outRecurs, $startRecurseFrom, false);
+					}
+
+					// selector sequence merging
+					if (! empty($before) && \count($new) > 1) {
+						$preSharedParts = $k > 0 ? \array_slice($before, 0, $k) : [];
+						$postSharedParts = $k > 0 ? \array_slice($before, $k) : $before;
+
+						list($betweenSharedParts, $nonBreakabl2) = $this->extractRelationshipFromFragment($afterBefore);
+
+						$result2 = array_merge(
+							$preSharedParts,
+							$betweenSharedParts,
+							$postSharedParts,
+							$nonBreakabl2,
+							$nonBreakableBefore,
+							$replacement,
+							$after
+						);
+
+						$this->pushOrMergeExtentedSelector($out, $result2);
+					}
+				}
+			}
+			array_pop($partsPile);
+		}
+
+		while (\count($outRecurs)) {
+			$result = array_shift($outRecurs);
+			$this->pushOrMergeExtentedSelector($out, $result);
+		}
+	}
+
+	/**
+	 * Test a part for being a pseudo selector
+	 *
+	 * @param string $part
+	 * @param array  $matches
+	 *
+	 * @return boolean
+	 */
+	protected function isPseudoSelector($part, &$matches)
+	{
+		if (
+			strpos($part, ':') === 0 &&
+			preg_match(",^::?([\w-]+)\((.+)\)$,", $part, $matches)
+		) {
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Push extended selector except if
+	 *  - this is a pseudo selector
+	 *  - same as previous
+	 *  - in a white list
+	 * in this case we merge the pseudo selector content
+	 *
+	 * @param array $out
+	 * @param array $extended
+	 */
+	protected function pushOrMergeExtentedSelector(&$out, $extended)
+	{
+		if (\count($out) && \count($extended) === 1 && \count(reset($extended)) === 1) {
+			$single = reset($extended);
+			$part = reset($single);
+
+			if (
+				$this->isPseudoSelector($part, $matchesExtended) &&
+				\in_array($matchesExtended[1], [ 'slotted' ])
+			) {
+				$prev = end($out);
+				$prev = $this->glueFunctionSelectors($prev);
+
+				if (\count($prev) === 1 && \count(reset($prev)) === 1) {
+					$single = reset($prev);
+					$part = reset($single);
+
+					if (
+						$this->isPseudoSelector($part, $matchesPrev) &&
+						$matchesPrev[1] === $matchesExtended[1]
+					) {
+						$extended = explode($matchesExtended[1] . '(', $matchesExtended[0], 2);
+						$extended[1] = $matchesPrev[2] . ', ' . $extended[1];
+						$extended = implode($matchesExtended[1] . '(', $extended);
+						$extended = [ [ $extended ]];
+						array_pop($out);
+					}
+				}
+			}
+		}
+		$out[] = $extended;
+	}
+
+	/**
+	 * Match extends single
+	 *
+	 * @param array   $rawSingle
+	 * @param array   $outOrigin
+	 * @param boolean $initial
+	 *
+	 * @return boolean
+	 */
+	protected function matchExtendsSingle($rawSingle, &$outOrigin, $initial = true)
+	{
+		$counts = [];
+		$single = [];
+
+		// simple usual cases, no need to do the whole trick
+		if (\in_array($rawSingle, [['>'],['+'],['~']])) {
+			return false;
+		}
+
+		foreach ($rawSingle as $part) {
+			// matches Number
+			if (! \is_string($part)) {
+				return false;
+			}
+
+			if (! preg_match('/^[\[.:#%]/', $part) && \count($single)) {
+				$single[\count($single) - 1] .= $part;
+			} else {
+				$single[] = $part;
+			}
+		}
+
+		$extendingDecoratedTag = false;
+
+		if (\count($single) > 1) {
+			$matches = null;
+			$extendingDecoratedTag = preg_match('/^[a-z0-9]+$/i', $single[0], $matches) ? $matches[0] : false;
+		}
+
+		$outOrigin = [];
+		$found = false;
+
+		foreach ($single as $k => $part) {
+			if (isset($this->extendsMap[$part])) {
+				foreach ($this->extendsMap[$part] as $idx) {
+					$counts[$idx] = isset($counts[$idx]) ? $counts[$idx] + 1 : 1;
+				}
+			}
+
+			if (
+				$initial &&
+				$this->isPseudoSelector($part, $matches) &&
+				! \in_array($matches[1], [ 'not' ])
+			) {
+				$buffer    = $matches[2];
+				$parser    = $this->parserFactory(__METHOD__);
+
+				if ($parser->parseSelector($buffer, $subSelectors)) {
+					foreach ($subSelectors as $ksub => $subSelector) {
+						$subExtended = [];
+						$this->matchExtends($subSelector, $subExtended, 0, false);
+
+						if ($subExtended) {
+							$subSelectorsExtended = $subSelectors;
+							$subSelectorsExtended[$ksub] = $subExtended;
+
+							foreach ($subSelectorsExtended as $ksse => $sse) {
+								$subSelectorsExtended[$ksse] = $this->collapseSelectors($sse);
+							}
+
+							$subSelectorsExtended = implode(', ', $subSelectorsExtended);
+							$singleExtended = $single;
+							$singleExtended[$k] = str_replace('(' . $buffer . ')', "($subSelectorsExtended)", $part);
+							$outOrigin[] = [ $singleExtended ];
+							$found = true;
+						}
+					}
+				}
+			}
+		}
+
+		foreach ($counts as $idx => $count) {
+			list($target, $origin, /* $block */) = $this->extends[$idx];
+
+			$origin = $this->glueFunctionSelectors($origin);
+
+			// check count
+			if ($count !== \count($target)) {
+				continue;
+			}
+
+			$this->extends[$idx][3] = true;
+
+			$rem = array_diff($single, $target);
+
+			foreach ($origin as $j => $new) {
+				// prevent infinite loop when target extends itself
+				if ($this->isSelfExtend($single, $origin) && ! $initial) {
+					return false;
+				}
+
+				$replacement = end($new);
+
+				// Extending a decorated tag with another tag is not possible.
+				if (
+					$extendingDecoratedTag && $replacement[0] != $extendingDecoratedTag &&
+					preg_match('/^[a-z0-9]+$/i', $replacement[0])
+				) {
+					unset($origin[$j]);
+					continue;
+				}
+
+				$combined = $this->combineSelectorSingle($replacement, $rem);
+
+				if (\count(array_diff($combined, $origin[$j][\count($origin[$j]) - 1]))) {
+					$origin[$j][\count($origin[$j]) - 1] = $combined;
+				}
+			}
+
+			$outOrigin = array_merge($outOrigin, $origin);
+
+			$found = true;
+		}
+
+		return $found;
+	}
+
+	/**
+	 * Extract a relationship from the fragment.
+	 *
+	 * When extracting the last portion of a selector we will be left with a
+	 * fragment which may end with a direction relationship combinator. This
+	 * method will extract the relationship fragment and return it along side
+	 * the rest.
+	 *
+	 * @param array $fragment The selector fragment maybe ending with a direction relationship combinator.
+	 *
+	 * @return array The selector without the relationship fragment if any, the relationship fragment.
+	 */
+	protected function extractRelationshipFromFragment(array $fragment)
+	{
+		$parents = [];
+		$children = [];
+
+		$j = $i = \count($fragment);
+
+		for (;;) {
+			$children = $j != $i ? \array_slice($fragment, $j, $i - $j) : [];
+			$parents  = \array_slice($fragment, 0, $j);
+			$slice    = end($parents);
+
+			if (empty($slice) || ! $this->isImmediateRelationshipCombinator($slice[0])) {
+				break;
+			}
+
+			$j -= 2;
+		}
+
+		return [$parents, $children];
+	}
+
+	/**
+	 * Combine selector single
+	 *
+	 * @param array $base
+	 * @param array $other
+	 *
+	 * @return array
+	 */
+	protected function combineSelectorSingle($base, $other)
+	{
+		$tag    = [];
+		$out    = [];
+		$wasTag = false;
+		$pseudo = [];
+
+		while (\count($other) && strpos(end($other), ':') === 0) {
+			array_unshift($pseudo, array_pop($other));
+		}
+
+		foreach ([array_reverse($base), array_reverse($other)] as $single) {
+			$rang = count($single);
+
+			foreach ($single as $part) {
+				if (preg_match('/^[\[:]/', $part)) {
+					$out[] = $part;
+					$wasTag = false;
+				} elseif (preg_match('/^[\.#]/', $part)) {
+					array_unshift($out, $part);
+					$wasTag = false;
+				} elseif (preg_match('/^[^_-]/', $part) && $rang === 1) {
+					$tag[] = $part;
+					$wasTag = true;
+				} elseif ($wasTag) {
+					$tag[\count($tag) - 1] .= $part;
+				} else {
+					array_unshift($out, $part);
+				}
+				$rang--;
+			}
+		}
+
+		if (\count($tag)) {
+			array_unshift($out, $tag[0]);
+		}
+
+		while (\count($pseudo)) {
+			$out[] = array_shift($pseudo);
+		}
+
+		return $out;
+	}
+
+	/**
+	 * Compile media
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $media
+	 */
+	protected function compileMedia(Block $media)
+	{
+		$this->pushEnv($media);
+
+		$mediaQueries = $this->compileMediaQuery($this->multiplyMedia($this->env));
+
+		if (! empty($mediaQueries) && $mediaQueries) {
+			$previousScope = $this->scope;
+			$parentScope = $this->mediaParent($this->scope);
+
+			foreach ($mediaQueries as $mediaQuery) {
+				$this->scope = $this->makeOutputBlock(Type::T_MEDIA, [$mediaQuery]);
+
+				$parentScope->children[] = $this->scope;
+				$parentScope = $this->scope;
+			}
+
+			// top level properties in a media cause it to be wrapped
+			$needsWrap = false;
+
+			foreach ($media->children as $child) {
+				$type = $child[0];
+
+				if (
+					$type !== Type::T_BLOCK &&
+					$type !== Type::T_MEDIA &&
+					$type !== Type::T_DIRECTIVE &&
+					$type !== Type::T_IMPORT
+				) {
+					$needsWrap = true;
+					break;
+				}
+			}
+
+			if ($needsWrap) {
+				$wrapped = new Block();
+				$wrapped->sourceName   = $media->sourceName;
+				$wrapped->sourceIndex  = $media->sourceIndex;
+				$wrapped->sourceLine   = $media->sourceLine;
+				$wrapped->sourceColumn = $media->sourceColumn;
+				$wrapped->selectors    = [];
+				$wrapped->comments     = [];
+				$wrapped->parent       = $media;
+				$wrapped->children     = $media->children;
+
+				$media->children = [[Type::T_BLOCK, $wrapped]];
+
+				if (isset($this->lineNumberStyle)) {
+					$annotation = $this->makeOutputBlock(Type::T_COMMENT);
+					$annotation->depth = 0;
+
+					$file = $this->sourceNames[$media->sourceIndex];
+					$line = $media->sourceLine;
+
+					switch ($this->lineNumberStyle) {
+						case static::LINE_COMMENTS:
+							$annotation->lines[] = '/* line ' . $line
+												 . ($file ? ', ' . $file : '')
+												 . ' */';
+							break;
+
+						case static::DEBUG_INFO:
+							$annotation->lines[] = '@media -sass-debug-info{'
+												 . ($file ? 'filename{font-family:"' . $file . '"}' : '')
+												 . 'line{font-family:' . $line . '}}';
+							break;
+					}
+
+					$this->scope->children[] = $annotation;
+				}
+			}
+
+			$this->compileChildrenNoReturn($media->children, $this->scope);
+
+			$this->scope = $previousScope;
+		}
+
+		$this->popEnv();
+	}
+
+	/**
+	 * Media parent
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
+	 *
+	 * @return \ScssPhp\ScssPhp\Formatter\OutputBlock
+	 */
+	protected function mediaParent(OutputBlock $scope)
+	{
+		while (! empty($scope->parent)) {
+			if (! empty($scope->type) && $scope->type !== Type::T_MEDIA) {
+				break;
+			}
+
+			$scope = $scope->parent;
+		}
+
+		return $scope;
+	}
+
+	/**
+	 * Compile directive
+	 *
+	 * @param \ScssPhp\ScssPhp\Block|array $block
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 */
+	protected function compileDirective($directive, OutputBlock $out)
+	{
+		if (\is_array($directive)) {
+			$s = '@' . $directive[0];
+
+			if (! empty($directive[1])) {
+				$s .= ' ' . $this->compileValue($directive[1]);
+			}
+
+			$this->appendRootDirective($s . ';', $out);
+		} else {
+			$s = '@' . $directive->name;
+
+			if (! empty($directive->value)) {
+				$s .= ' ' . $this->compileValue($directive->value);
+			}
+
+			if ($directive->name === 'keyframes' || substr($directive->name, -10) === '-keyframes') {
+				$this->compileKeyframeBlock($directive, [$s]);
+			} else {
+				$this->compileNestedBlock($directive, [$s]);
+			}
+		}
+	}
+
+	/**
+	 * Compile at-root
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $block
+	 */
+	protected function compileAtRoot(Block $block)
+	{
+		$env     = $this->pushEnv($block);
+		$envs    = $this->compactEnv($env);
+		list($with, $without) = $this->compileWith(isset($block->with) ? $block->with : null);
+
+		// wrap inline selector
+		if ($block->selector) {
+			$wrapped = new Block();
+			$wrapped->sourceName   = $block->sourceName;
+			$wrapped->sourceIndex  = $block->sourceIndex;
+			$wrapped->sourceLine   = $block->sourceLine;
+			$wrapped->sourceColumn = $block->sourceColumn;
+			$wrapped->selectors    = $block->selector;
+			$wrapped->comments     = [];
+			$wrapped->parent       = $block;
+			$wrapped->children     = $block->children;
+			$wrapped->selfParent   = $block->selfParent;
+
+			$block->children = [[Type::T_BLOCK, $wrapped]];
+			$block->selector = null;
+		}
+
+		$selfParent = $block->selfParent;
+
+		if (
+			! $block->selfParent->selectors &&
+			isset($block->parent) && $block->parent &&
+			isset($block->parent->selectors) && $block->parent->selectors
+		) {
+			$selfParent = $block->parent;
+		}
+
+		$this->env = $this->filterWithWithout($envs, $with, $without);
+
+		$saveScope   = $this->scope;
+		$this->scope = $this->filterScopeWithWithout($saveScope, $with, $without);
+
+		// propagate selfParent to the children where they still can be useful
+		$this->compileChildrenNoReturn($block->children, $this->scope, $selfParent);
+
+		$this->scope = $this->completeScope($this->scope, $saveScope);
+		$this->scope = $saveScope;
+		$this->env   = $this->extractEnv($envs);
+
+		$this->popEnv();
+	}
+
+	/**
+	 * Filter at-root scope depending of with/without option
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
+	 * @param array                                  $with
+	 * @param array                                  $without
+	 *
+	 * @return mixed
+	 */
+	protected function filterScopeWithWithout($scope, $with, $without)
+	{
+		$filteredScopes = [];
+		$childStash = [];
+
+		if ($scope->type === TYPE::T_ROOT) {
+			return $scope;
+		}
+
+		// start from the root
+		while ($scope->parent && $scope->parent->type !== TYPE::T_ROOT) {
+			array_unshift($childStash, $scope);
+			$scope = $scope->parent;
+		}
+
+		for (;;) {
+			if (! $scope) {
+				break;
+			}
+
+			if ($this->isWith($scope, $with, $without)) {
+				$s = clone $scope;
+				$s->children = [];
+				$s->lines    = [];
+				$s->parent   = null;
+
+				if ($s->type !== Type::T_MEDIA && $s->type !== Type::T_DIRECTIVE) {
+					$s->selectors = [];
+				}
+
+				$filteredScopes[] = $s;
+			}
+
+			if (\count($childStash)) {
+				$scope = array_shift($childStash);
+			} elseif ($scope->children) {
+				$scope = end($scope->children);
+			} else {
+				$scope = null;
+			}
+		}
+
+		if (! \count($filteredScopes)) {
+			return $this->rootBlock;
+		}
+
+		$newScope = array_shift($filteredScopes);
+		$newScope->parent = $this->rootBlock;
+
+		$this->rootBlock->children[] = $newScope;
+
+		$p = &$newScope;
+
+		while (\count($filteredScopes)) {
+			$s = array_shift($filteredScopes);
+			$s->parent = $p;
+			$p->children[] = $s;
+			$newScope = &$p->children[0];
+			$p = &$p->children[0];
+		}
+
+		return $newScope;
+	}
+
+	/**
+	 * found missing selector from a at-root compilation in the previous scope
+	 * (if at-root is just enclosing a property, the selector is in the parent tree)
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $previousScope
+	 *
+	 * @return mixed
+	 */
+	protected function completeScope($scope, $previousScope)
+	{
+		if (! $scope->type && (! $scope->selectors || ! \count($scope->selectors)) && \count($scope->lines)) {
+			$scope->selectors = $this->findScopeSelectors($previousScope, $scope->depth);
+		}
+
+		if ($scope->children) {
+			foreach ($scope->children as $k => $c) {
+				$scope->children[$k] = $this->completeScope($c, $previousScope);
+			}
+		}
+
+		return $scope;
+	}
+
+	/**
+	 * Find a selector by the depth node in the scope
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $scope
+	 * @param integer                                $depth
+	 *
+	 * @return array
+	 */
+	protected function findScopeSelectors($scope, $depth)
+	{
+		if ($scope->depth === $depth && $scope->selectors) {
+			return $scope->selectors;
+		}
+
+		if ($scope->children) {
+			foreach (array_reverse($scope->children) as $c) {
+				if ($s = $this->findScopeSelectors($c, $depth)) {
+					return $s;
+				}
+			}
+		}
+
+		return [];
+	}
+
+	/**
+	 * Compile @at-root's with: inclusion / without: exclusion into 2 lists uses to filter scope/env later
+	 *
+	 * @param array $withCondition
+	 *
+	 * @return array
+	 */
+	protected function compileWith($withCondition)
+	{
+		// just compile what we have in 2 lists
+		$with = [];
+		$without = ['rule' => true];
+
+		if ($withCondition) {
+			if ($withCondition[0] === Type::T_INTERPOLATE) {
+				$w = $this->compileValue($withCondition);
+
+				$buffer = "($w)";
+				$parser = $this->parserFactory(__METHOD__);
+
+				if ($parser->parseValue($buffer, $reParsedWith)) {
+					$withCondition = $reParsedWith;
+				}
+			}
+
+			if ($this->libMapHasKey([$withCondition, static::$with])) {
+				$without = []; // cancel the default
+				$list = $this->coerceList($this->libMapGet([$withCondition, static::$with]));
+
+				foreach ($list[2] as $item) {
+					$keyword = $this->compileStringContent($this->coerceString($item));
+
+					$with[$keyword] = true;
+				}
+			}
+
+			if ($this->libMapHasKey([$withCondition, static::$without])) {
+				$without = []; // cancel the default
+				$list = $this->coerceList($this->libMapGet([$withCondition, static::$without]));
+
+				foreach ($list[2] as $item) {
+					$keyword = $this->compileStringContent($this->coerceString($item));
+
+					$without[$keyword] = true;
+				}
+			}
+		}
+
+		return [$with, $without];
+	}
+
+	/**
+	 * Filter env stack
+	 *
+	 * @param array $envs
+	 * @param array $with
+	 * @param array $without
+	 *
+	 * @return \ScssPhp\ScssPhp\Compiler\Environment
+	 */
+	protected function filterWithWithout($envs, $with, $without)
+	{
+		$filtered = [];
+
+		foreach ($envs as $e) {
+			if ($e->block && ! $this->isWith($e->block, $with, $without)) {
+				$ec = clone $e;
+				$ec->block     = null;
+				$ec->selectors = [];
+
+				$filtered[] = $ec;
+			} else {
+				$filtered[] = $e;
+			}
+		}
+
+		return $this->extractEnv($filtered);
+	}
+
+	/**
+	 * Filter WITH rules
+	 *
+	 * @param \ScssPhp\ScssPhp\Block|\ScssPhp\ScssPhp\Formatter\OutputBlock $block
+	 * @param array                                                         $with
+	 * @param array                                                         $without
+	 *
+	 * @return boolean
+	 */
+	protected function isWith($block, $with, $without)
+	{
+		if (isset($block->type)) {
+			if ($block->type === Type::T_MEDIA) {
+				return $this->testWithWithout('media', $with, $without);
+			}
+
+			if ($block->type === Type::T_DIRECTIVE) {
+				if (isset($block->name)) {
+					return $this->testWithWithout($block->name, $with, $without);
+				} elseif (isset($block->selectors) && preg_match(',@(\w+),ims', json_encode($block->selectors), $m)) {
+					return $this->testWithWithout($m[1], $with, $without);
+				} else {
+					return $this->testWithWithout('???', $with, $without);
+				}
+			}
+		} elseif (isset($block->selectors)) {
+			// a selector starting with number is a keyframe rule
+			if (\count($block->selectors)) {
+				$s = reset($block->selectors);
+
+				while (\is_array($s)) {
+					$s = reset($s);
+				}
+
+				if (\is_object($s) && $s instanceof Node\Number) {
+					return $this->testWithWithout('keyframes', $with, $without);
+				}
+			}
+
+			return $this->testWithWithout('rule', $with, $without);
+		}
+
+		return true;
+	}
+
+	/**
+	 * Test a single type of block against with/without lists
+	 *
+	 * @param string $what
+	 * @param array  $with
+	 * @param array  $without
+	 *
+	 * @return boolean
+	 *   true if the block should be kept, false to reject
+	 */
+	protected function testWithWithout($what, $with, $without)
+	{
+		// if without, reject only if in the list (or 'all' is in the list)
+		if (\count($without)) {
+			return (isset($without[$what]) || isset($without['all'])) ? false : true;
+		}
+
+		// otherwise reject all what is not in the with list
+		return (isset($with[$what]) || isset($with['all'])) ? true : false;
+	}
+
+
+	/**
+	 * Compile keyframe block
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $block
+	 * @param array                  $selectors
+	 */
+	protected function compileKeyframeBlock(Block $block, $selectors)
+	{
+		$env = $this->pushEnv($block);
+
+		$envs = $this->compactEnv($env);
+
+		$this->env = $this->extractEnv(array_filter($envs, function (Environment $e) {
+			return ! isset($e->block->selectors);
+		}));
+
+		$this->scope = $this->makeOutputBlock($block->type, $selectors);
+		$this->scope->depth = 1;
+		$this->scope->parent->children[] = $this->scope;
+
+		$this->compileChildrenNoReturn($block->children, $this->scope);
+
+		$this->scope = $this->scope->parent;
+		$this->env   = $this->extractEnv($envs);
+
+		$this->popEnv();
+	}
+
+	/**
+	 * Compile nested properties lines
+	 *
+	 * @param \ScssPhp\ScssPhp\Block                 $block
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 */
+	protected function compileNestedPropertiesBlock(Block $block, OutputBlock $out)
+	{
+		$prefix = $this->compileValue($block->prefix) . '-';
+
+		$nested = $this->makeOutputBlock($block->type);
+		$nested->parent = $out;
+
+		if ($block->hasValue) {
+			$nested->depth = $out->depth + 1;
+		}
+
+		$out->children[] = $nested;
+
+		foreach ($block->children as $child) {
+			switch ($child[0]) {
+				case Type::T_ASSIGN:
+					array_unshift($child[1][2], $prefix);
+					break;
+
+				case Type::T_NESTED_PROPERTY:
+					array_unshift($child[1]->prefix[2], $prefix);
+					break;
+			}
+
+			$this->compileChild($child, $nested);
+		}
+	}
+
+	/**
+	 * Compile nested block
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $block
+	 * @param array                  $selectors
+	 */
+	protected function compileNestedBlock(Block $block, $selectors)
+	{
+		$this->pushEnv($block);
+
+		$this->scope = $this->makeOutputBlock($block->type, $selectors);
+		$this->scope->parent->children[] = $this->scope;
+
+		// wrap assign children in a block
+		// except for @font-face
+		if ($block->type !== Type::T_DIRECTIVE || $block->name !== 'font-face') {
+			// need wrapping?
+			$needWrapping = false;
+
+			foreach ($block->children as $child) {
+				if ($child[0] === Type::T_ASSIGN) {
+					$needWrapping = true;
+					break;
+				}
+			}
+
+			if ($needWrapping) {
+				$wrapped = new Block();
+				$wrapped->sourceName   = $block->sourceName;
+				$wrapped->sourceIndex  = $block->sourceIndex;
+				$wrapped->sourceLine   = $block->sourceLine;
+				$wrapped->sourceColumn = $block->sourceColumn;
+				$wrapped->selectors    = [];
+				$wrapped->comments     = [];
+				$wrapped->parent       = $block;
+				$wrapped->children     = $block->children;
+				$wrapped->selfParent   = $block->selfParent;
+
+				$block->children = [[Type::T_BLOCK, $wrapped]];
+			}
+		}
+
+		$this->compileChildrenNoReturn($block->children, $this->scope);
+
+		$this->scope = $this->scope->parent;
+
+		$this->popEnv();
+	}
+
+	/**
+	 * Recursively compiles a block.
+	 *
+	 * A block is analogous to a CSS block in most cases. A single SCSS document
+	 * is encapsulated in a block when parsed, but it does not have parent tags
+	 * so all of its children appear on the root level when compiled.
+	 *
+	 * Blocks are made up of selectors and children.
+	 *
+	 * The children of a block are just all the blocks that are defined within.
+	 *
+	 * Compiling the block involves pushing a fresh environment on the stack,
+	 * and iterating through the props, compiling each one.
+	 *
+	 * @see Compiler::compileChild()
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $block
+	 */
+	protected function compileBlock(Block $block)
+	{
+		$env = $this->pushEnv($block);
+		$env->selectors = $this->evalSelectors($block->selectors);
+
+		$out = $this->makeOutputBlock(null);
+
+		if (isset($this->lineNumberStyle) && \count($env->selectors) && \count($block->children)) {
+			$annotation = $this->makeOutputBlock(Type::T_COMMENT);
+			$annotation->depth = 0;
+
+			$file = $this->sourceNames[$block->sourceIndex];
+			$line = $block->sourceLine;
+
+			switch ($this->lineNumberStyle) {
+				case static::LINE_COMMENTS:
+					$annotation->lines[] = '/* line ' . $line
+										 . ($file ? ', ' . $file : '')
+										 . ' */';
+					break;
+
+				case static::DEBUG_INFO:
+					$annotation->lines[] = '@media -sass-debug-info{'
+										 . ($file ? 'filename{font-family:"' . $file . '"}' : '')
+										 . 'line{font-family:' . $line . '}}';
+					break;
+			}
+
+			$this->scope->children[] = $annotation;
+		}
+
+		$this->scope->children[] = $out;
+
+		if (\count($block->children)) {
+			$out->selectors = $this->multiplySelectors($env, $block->selfParent);
+
+			// propagate selfParent to the children where they still can be useful
+			$selfParentSelectors = null;
+
+			if (isset($block->selfParent->selectors)) {
+				$selfParentSelectors = $block->selfParent->selectors;
+				$block->selfParent->selectors = $out->selectors;
+			}
+
+			$this->compileChildrenNoReturn($block->children, $out, $block->selfParent);
+
+			// and revert for the following children of the same block
+			if ($selfParentSelectors) {
+				$block->selfParent->selectors = $selfParentSelectors;
+			}
+		}
+
+		$this->popEnv();
+	}
+
+
+	/**
+	 * Compile the value of a comment that can have interpolation
+	 *
+	 * @param array   $value
+	 * @param boolean $pushEnv
+	 *
+	 * @return array|mixed|string
+	 */
+	protected function compileCommentValue($value, $pushEnv = false)
+	{
+		$c = $value[1];
+
+		if (isset($value[2])) {
+			if ($pushEnv) {
+				$this->pushEnv();
+			}
+
+			$ignoreCallStackMessage = $this->ignoreCallStackMessage;
+			$this->ignoreCallStackMessage = true;
+
+			try {
+				$c = $this->compileValue($value[2]);
+			} catch (\Exception $e) {
+				// ignore error in comment compilation which are only interpolation
+			}
+
+			$this->ignoreCallStackMessage = $ignoreCallStackMessage;
+
+			if ($pushEnv) {
+				$this->popEnv();
+			}
+		}
+
+		return $c;
+	}
+
+	/**
+	 * Compile root level comment
+	 *
+	 * @param array $block
+	 */
+	protected function compileComment($block)
+	{
+		$out = $this->makeOutputBlock(Type::T_COMMENT);
+		$out->lines[] = $this->compileCommentValue($block, true);
+
+		$this->scope->children[] = $out;
+	}
+
+	/**
+	 * Evaluate selectors
+	 *
+	 * @param array $selectors
+	 *
+	 * @return array
+	 */
+	protected function evalSelectors($selectors)
+	{
+		$this->shouldEvaluate = false;
+
+		$selectors = array_map([$this, 'evalSelector'], $selectors);
+
+		// after evaluating interpolates, we might need a second pass
+		if ($this->shouldEvaluate) {
+			$selectors = $this->replaceSelfSelector($selectors, '&');
+			$buffer    = $this->collapseSelectors($selectors);
+			$parser    = $this->parserFactory(__METHOD__);
+
+			if ($parser->parseSelector($buffer, $newSelectors)) {
+				$selectors = array_map([$this, 'evalSelector'], $newSelectors);
+			}
+		}
+
+		return $selectors;
+	}
+
+	/**
+	 * Evaluate selector
+	 *
+	 * @param array $selector
+	 *
+	 * @return array
+	 */
+	protected function evalSelector($selector)
+	{
+		return array_map([$this, 'evalSelectorPart'], $selector);
+	}
+
+	/**
+	 * Evaluate selector part; replaces all the interpolates, stripping quotes
+	 *
+	 * @param array $part
+	 *
+	 * @return array
+	 */
+	protected function evalSelectorPart($part)
+	{
+		foreach ($part as &$p) {
+			if (\is_array($p) && ($p[0] === Type::T_INTERPOLATE || $p[0] === Type::T_STRING)) {
+				$p = $this->compileValue($p);
+
+				// force re-evaluation
+				if (strpos($p, '&') !== false || strpos($p, ',') !== false) {
+					$this->shouldEvaluate = true;
+				}
+			} elseif (
+				\is_string($p) && \strlen($p) >= 2 &&
+				($first = $p[0]) && ($first === '"' || $first === "'") &&
+				substr($p, -1) === $first
+			) {
+				$p = substr($p, 1, -1);
+			}
+		}
+
+		return $this->flattenSelectorSingle($part);
+	}
+
+	/**
+	 * Collapse selectors
+	 *
+	 * @param array   $selectors
+	 * @param boolean $selectorFormat
+	 *   if false return a collapsed string
+	 *   if true return an array description of a structured selector
+	 *
+	 * @return string
+	 */
+	protected function collapseSelectors($selectors, $selectorFormat = false)
+	{
+		$parts = [];
+
+		foreach ($selectors as $selector) {
+			$output = [];
+			$glueNext = false;
+
+			foreach ($selector as $node) {
+				$compound = '';
+
+				array_walk_recursive(
+					$node,
+					function ($value, $key) use (&$compound) {
+						$compound .= $value;
+					}
+				);
+
+				if ($selectorFormat && $this->isImmediateRelationshipCombinator($compound)) {
+					if (\count($output)) {
+						$output[\count($output) - 1] .= ' ' . $compound;
+					} else {
+						$output[] = $compound;
+					}
+
+					$glueNext = true;
+				} elseif ($glueNext) {
+					$output[\count($output) - 1] .= ' ' . $compound;
+					$glueNext = false;
+				} else {
+					$output[] = $compound;
+				}
+			}
+
+			if ($selectorFormat) {
+				foreach ($output as &$o) {
+					$o = [Type::T_STRING, '', [$o]];
+				}
+
+				$output = [Type::T_LIST, ' ', $output];
+			} else {
+				$output = implode(' ', $output);
+			}
+
+			$parts[] = $output;
+		}
+
+		if ($selectorFormat) {
+			$parts = [Type::T_LIST, ',', $parts];
+		} else {
+			$parts = implode(', ', $parts);
+		}
+
+		return $parts;
+	}
+
+	/**
+	 * Parse down the selector and revert [self] to "&" before a reparsing
+	 *
+	 * @param array $selectors
+	 *
+	 * @return array
+	 */
+	protected function replaceSelfSelector($selectors, $replace = null)
+	{
+		foreach ($selectors as &$part) {
+			if (\is_array($part)) {
+				if ($part === [Type::T_SELF]) {
+					if (\is_null($replace)) {
+						$replace = $this->reduce([Type::T_SELF]);
+						$replace = $this->compileValue($replace);
+					}
+					$part = $replace;
+				} else {
+					$part = $this->replaceSelfSelector($part, $replace);
+				}
+			}
+		}
+
+		return $selectors;
+	}
+
+	/**
+	 * Flatten selector single; joins together .classes and #ids
+	 *
+	 * @param array $single
+	 *
+	 * @return array
+	 */
+	protected function flattenSelectorSingle($single)
+	{
+		$joined = [];
+
+		foreach ($single as $part) {
+			if (
+				empty($joined) ||
+				! \is_string($part) ||
+				preg_match('/[\[.:#%]/', $part)
+			) {
+				$joined[] = $part;
+				continue;
+			}
+
+			if (\is_array(end($joined))) {
+				$joined[] = $part;
+			} else {
+				$joined[\count($joined) - 1] .= $part;
+			}
+		}
+
+		return $joined;
+	}
+
+	/**
+	 * Compile selector to string; self(&) should have been replaced by now
+	 *
+	 * @param string|array $selector
+	 *
+	 * @return string
+	 */
+	protected function compileSelector($selector)
+	{
+		if (! \is_array($selector)) {
+			return $selector; // media and the like
+		}
+
+		return implode(
+			' ',
+			array_map(
+				[$this, 'compileSelectorPart'],
+				$selector
+			)
+		);
+	}
+
+	/**
+	 * Compile selector part
+	 *
+	 * @param array $piece
+	 *
+	 * @return string
+	 */
+	protected function compileSelectorPart($piece)
+	{
+		foreach ($piece as &$p) {
+			if (! \is_array($p)) {
+				continue;
+			}
+
+			switch ($p[0]) {
+				case Type::T_SELF:
+					$p = '&';
+					break;
+
+				default:
+					$p = $this->compileValue($p);
+					break;
+			}
+		}
+
+		return implode($piece);
+	}
+
+	/**
+	 * Has selector placeholder?
+	 *
+	 * @param array $selector
+	 *
+	 * @return boolean
+	 */
+	protected function hasSelectorPlaceholder($selector)
+	{
+		if (! \is_array($selector)) {
+			return false;
+		}
+
+		foreach ($selector as $parts) {
+			foreach ($parts as $part) {
+				if (\strlen($part) && '%' === $part[0]) {
+					return true;
+				}
+			}
+		}
+
+		return false;
+	}
+
+	protected function pushCallStack($name = '')
+	{
+		$this->callStack[] = [
+		  'n' => $name,
+		  Parser::SOURCE_INDEX => $this->sourceIndex,
+		  Parser::SOURCE_LINE => $this->sourceLine,
+		  Parser::SOURCE_COLUMN => $this->sourceColumn
+		];
+
+		// infinite calling loop
+		if (\count($this->callStack) > 25000) {
+			// not displayed but you can var_dump it to deep debug
+			$msg = $this->callStackMessage(true, 100);
+			$msg = 'Infinite calling loop';
+
+			throw $this->error($msg);
+		}
+	}
+
+	protected function popCallStack()
+	{
+		array_pop($this->callStack);
+	}
+
+	/**
+	 * Compile children and return result
+	 *
+	 * @param array                                  $stms
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 * @param string                                 $traceName
+	 *
+	 * @return array|null
+	 */
+	protected function compileChildren($stms, OutputBlock $out, $traceName = '')
+	{
+		$this->pushCallStack($traceName);
+
+		foreach ($stms as $stm) {
+			$ret = $this->compileChild($stm, $out);
+
+			if (isset($ret)) {
+				$this->popCallStack();
+
+				return $ret;
+			}
+		}
+
+		$this->popCallStack();
+
+		return null;
+	}
+
+	/**
+	 * Compile children and throw exception if unexpected @return
+	 *
+	 * @param array                                  $stms
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 * @param \ScssPhp\ScssPhp\Block                 $selfParent
+	 * @param string                                 $traceName
+	 *
+	 * @throws \Exception
+	 */
+	protected function compileChildrenNoReturn($stms, OutputBlock $out, $selfParent = null, $traceName = '')
+	{
+		$this->pushCallStack($traceName);
+
+		foreach ($stms as $stm) {
+			if ($selfParent && isset($stm[1]) && \is_object($stm[1]) && $stm[1] instanceof Block) {
+				$stm[1]->selfParent = $selfParent;
+				$ret = $this->compileChild($stm, $out);
+				$stm[1]->selfParent = null;
+			} elseif ($selfParent && \in_array($stm[0], [TYPE::T_INCLUDE, TYPE::T_EXTEND])) {
+				$stm['selfParent'] = $selfParent;
+				$ret = $this->compileChild($stm, $out);
+				unset($stm['selfParent']);
+			} else {
+				$ret = $this->compileChild($stm, $out);
+			}
+
+			if (isset($ret)) {
+				throw $this->error('@return may only be used within a function');
+			}
+		}
+
+		$this->popCallStack();
+	}
+
+
+	/**
+	 * evaluate media query : compile internal value keeping the structure inchanged
+	 *
+	 * @param array $queryList
+	 *
+	 * @return array
+	 */
+	protected function evaluateMediaQuery($queryList)
+	{
+		static $parser = null;
+
+		$outQueryList = [];
+
+		foreach ($queryList as $kql => $query) {
+			$shouldReparse = false;
+
+			foreach ($query as $kq => $q) {
+				for ($i = 1; $i < \count($q); $i++) {
+					$value = $this->compileValue($q[$i]);
+
+					// the parser had no mean to know if media type or expression if it was an interpolation
+					// so you need to reparse if the T_MEDIA_TYPE looks like anything else a media type
+					if (
+						$q[0] == Type::T_MEDIA_TYPE &&
+						(strpos($value, '(') !== false ||
+						strpos($value, ')') !== false ||
+						strpos($value, ':') !== false ||
+						strpos($value, ',') !== false)
+					) {
+						$shouldReparse = true;
+					}
+
+					$queryList[$kql][$kq][$i] = [Type::T_KEYWORD, $value];
+				}
+			}
+
+			if ($shouldReparse) {
+				if (\is_null($parser)) {
+					$parser = $this->parserFactory(__METHOD__);
+				}
+
+				$queryString = $this->compileMediaQuery([$queryList[$kql]]);
+				$queryString = reset($queryString);
+
+				if (strpos($queryString, '@media ') === 0) {
+					$queryString = substr($queryString, 7);
+					$queries = [];
+
+					if ($parser->parseMediaQueryList($queryString, $queries)) {
+						$queries = $this->evaluateMediaQuery($queries[2]);
+
+						while (\count($queries)) {
+							$outQueryList[] = array_shift($queries);
+						}
+
+						continue;
+					}
+				}
+			}
+
+			$outQueryList[] = $queryList[$kql];
+		}
+
+		return $outQueryList;
+	}
+
+	/**
+	 * Compile media query
+	 *
+	 * @param array $queryList
+	 *
+	 * @return array
+	 */
+	protected function compileMediaQuery($queryList)
+	{
+		$start   = '@media ';
+		$default = trim($start);
+		$out     = [];
+		$current = '';
+
+		foreach ($queryList as $query) {
+			$type = null;
+			$parts = [];
+
+			$mediaTypeOnly = true;
+
+			foreach ($query as $q) {
+				if ($q[0] !== Type::T_MEDIA_TYPE) {
+					$mediaTypeOnly = false;
+					break;
+				}
+			}
+
+			foreach ($query as $q) {
+				switch ($q[0]) {
+					case Type::T_MEDIA_TYPE:
+						$newType = array_map([$this, 'compileValue'], \array_slice($q, 1));
+
+						// combining not and anything else than media type is too risky and should be avoided
+						if (! $mediaTypeOnly) {
+							if (\in_array(Type::T_NOT, $newType) || ($type && \in_array(Type::T_NOT, $type) )) {
+								if ($type) {
+									array_unshift($parts, implode(' ', array_filter($type)));
+								}
+
+								if (! empty($parts)) {
+									if (\strlen($current)) {
+										$current .= $this->formatter->tagSeparator;
+									}
+
+									$current .= implode(' and ', $parts);
+								}
+
+								if ($current) {
+									$out[] = $start . $current;
+								}
+
+								$current = '';
+								$type    = null;
+								$parts   = [];
+							}
+						}
+
+						if ($newType === ['all'] && $default) {
+							$default = $start . 'all';
+						}
+
+						// all can be safely ignored and mixed with whatever else
+						if ($newType !== ['all']) {
+							if ($type) {
+								$type = $this->mergeMediaTypes($type, $newType);
+
+								if (empty($type)) {
+									// merge failed : ignore this query that is not valid, skip to the next one
+									$parts = [];
+									$default = ''; // if everything fail, no @media at all
+									continue 3;
+								}
+							} else {
+								$type = $newType;
+							}
+						}
+						break;
+
+					case Type::T_MEDIA_EXPRESSION:
+						if (isset($q[2])) {
+							$parts[] = '('
+								. $this->compileValue($q[1])
+								. $this->formatter->assignSeparator
+								. $this->compileValue($q[2])
+								. ')';
+						} else {
+							$parts[] = '('
+								. $this->compileValue($q[1])
+								. ')';
+						}
+						break;
+
+					case Type::T_MEDIA_VALUE:
+						$parts[] = $this->compileValue($q[1]);
+						break;
+				}
+			}
+
+			if ($type) {
+				array_unshift($parts, implode(' ', array_filter($type)));
+			}
+
+			if (! empty($parts)) {
+				if (\strlen($current)) {
+					$current .= $this->formatter->tagSeparator;
+				}
+
+				$current .= implode(' and ', $parts);
+			}
+		}
+
+		if ($current) {
+			$out[] = $start . $current;
+		}
+
+		// no @media type except all, and no conflict?
+		if (! $out && $default) {
+			$out[] = $default;
+		}
+
+		return $out;
+	}
+
+	/**
+	 * Merge direct relationships between selectors
+	 *
+	 * @param array $selectors1
+	 * @param array $selectors2
+	 *
+	 * @return array
+	 */
+	protected function mergeDirectRelationships($selectors1, $selectors2)
+	{
+		if (empty($selectors1) || empty($selectors2)) {
+			return array_merge($selectors1, $selectors2);
+		}
+
+		$part1 = end($selectors1);
+		$part2 = end($selectors2);
+
+		if (! $this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
+			return array_merge($selectors1, $selectors2);
+		}
+
+		$merged = [];
+
+		do {
+			$part1 = array_pop($selectors1);
+			$part2 = array_pop($selectors2);
+
+			if (! $this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
+				if ($this->isImmediateRelationshipCombinator(reset($merged)[0])) {
+					array_unshift($merged, [$part1[0] . $part2[0]]);
+					$merged = array_merge($selectors1, $selectors2, $merged);
+				} else {
+					$merged = array_merge($selectors1, [$part1], $selectors2, [$part2], $merged);
+				}
+
+				break;
+			}
+
+			array_unshift($merged, $part1);
+		} while (! empty($selectors1) && ! empty($selectors2));
+
+		return $merged;
+	}
+
+	/**
+	 * Merge media types
+	 *
+	 * @param array $type1
+	 * @param array $type2
+	 *
+	 * @return array|null
+	 */
+	protected function mergeMediaTypes($type1, $type2)
+	{
+		if (empty($type1)) {
+			return $type2;
+		}
+
+		if (empty($type2)) {
+			return $type1;
+		}
+
+		if (\count($type1) > 1) {
+			$m1 = strtolower($type1[0]);
+			$t1 = strtolower($type1[1]);
+		} else {
+			$m1 = '';
+			$t1 = strtolower($type1[0]);
+		}
+
+		if (\count($type2) > 1) {
+			$m2 = strtolower($type2[0]);
+			$t2 = strtolower($type2[1]);
+		} else {
+			$m2 = '';
+			$t2 = strtolower($type2[0]);
+		}
+
+		if (($m1 === Type::T_NOT) ^ ($m2 === Type::T_NOT)) {
+			if ($t1 === $t2) {
+				return null;
+			}
+
+			return [
+				$m1 === Type::T_NOT ? $m2 : $m1,
+				$m1 === Type::T_NOT ? $t2 : $t1,
+			];
+		}
+
+		if ($m1 === Type::T_NOT && $m2 === Type::T_NOT) {
+			// CSS has no way of representing "neither screen nor print"
+			if ($t1 !== $t2) {
+				return null;
+			}
+
+			return [Type::T_NOT, $t1];
+		}
+
+		if ($t1 !== $t2) {
+			return null;
+		}
+
+		// t1 == t2, neither m1 nor m2 are "not"
+		return [empty($m1) ? $m2 : $m1, $t1];
+	}
+
+	/**
+	 * Compile import; returns true if the value was something that could be imported
+	 *
+	 * @param array                                  $rawPath
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 * @param boolean                                $once
+	 *
+	 * @return boolean
+	 */
+	protected function compileImport($rawPath, OutputBlock $out, $once = false)
+	{
+		if ($rawPath[0] === Type::T_STRING) {
+			$path = $this->compileStringContent($rawPath);
+
+			if (strpos($path, 'url(') !== 0 && $path = $this->findImport($path)) {
+				if (! $once || ! \in_array($path, $this->importedFiles)) {
+					$this->importFile($path, $out);
+					$this->importedFiles[] = $path;
+				}
+
+				return true;
+			}
+
+			$this->appendRootDirective('@import ' . $this->compileImportPath($rawPath) . ';', $out);
+
+			return false;
+		}
+
+		if ($rawPath[0] === Type::T_LIST) {
+			// handle a list of strings
+			if (\count($rawPath[2]) === 0) {
+				return false;
+			}
+
+			foreach ($rawPath[2] as $path) {
+				if ($path[0] !== Type::T_STRING) {
+					$this->appendRootDirective('@import ' . $this->compileImportPath($rawPath) . ';', $out);
+
+					return false;
+				}
+			}
+
+			foreach ($rawPath[2] as $path) {
+				$this->compileImport($path, $out, $once);
+			}
+
+			return true;
+		}
+
+		$this->appendRootDirective('@import ' . $this->compileImportPath($rawPath) . ';', $out);
+
+		return false;
+	}
+
+	/**
+	 * @param $rawPath
+	 * @return string
+	 * @throws CompilerException
+	 */
+	protected function compileImportPath($rawPath)
+	{
+		$path = $this->compileValue($rawPath);
+
+		// case url() without quotes : supress \r \n remaining in the path
+		// if this is a real string there can not be CR or LF char
+		if (strpos($path, 'url(') === 0) {
+			$path = str_replace(array("\r", "\n"), array('', ' '), $path);
+		} else {
+			// if this is a file name in a string, spaces shoudl be escaped
+			$path = $this->reduce($rawPath);
+			$path = $this->escapeImportPathString($path);
+			$path = $this->compileValue($path);
+		}
+
+		return $path;
+	}
+
+	/**
+	 * @param array $path
+	 * @return array
+	 * @throws CompilerException
+	 */
+	protected function escapeImportPathString($path)
+	{
+		switch ($path[0]) {
+			case Type::T_LIST:
+				foreach ($path[2] as $k => $v) {
+					$path[2][$k] = $this->escapeImportPathString($v);
+				}
+				break;
+			case Type::T_STRING:
+				if ($path[1]) {
+					$path = $this->compileValue($path);
+					$path = str_replace(' ', '\\ ', $path);
+					$path = [Type::T_KEYWORD, $path];
+				}
+				break;
+		}
+
+		return $path;
+	}
+
+	/**
+	 * Append a root directive like @import or @charset as near as the possible from the source code
+	 * (keeping before comments, @import and @charset coming before in the source code)
+	 *
+	 * @param string                                        $line
+	 * @param @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 * @param array                                         $allowed
+	 */
+	protected function appendRootDirective($line, $out, $allowed = [Type::T_COMMENT])
+	{
+		$root = $out;
+
+		while ($root->parent) {
+			$root = $root->parent;
+		}
+
+		$i = 0;
+
+		while ($i < \count($root->children)) {
+			if (! isset($root->children[$i]->type) || ! \in_array($root->children[$i]->type, $allowed)) {
+				break;
+			}
+
+			$i++;
+		}
+
+		// remove incompatible children from the bottom of the list
+		$saveChildren = [];
+
+		while ($i < \count($root->children)) {
+			$saveChildren[] = array_pop($root->children);
+		}
+
+		// insert the directive as a comment
+		$child = $this->makeOutputBlock(Type::T_COMMENT);
+		$child->lines[]      = $line;
+		$child->sourceName   = $this->sourceNames[$this->sourceIndex];
+		$child->sourceLine   = $this->sourceLine;
+		$child->sourceColumn = $this->sourceColumn;
+
+		$root->children[] = $child;
+
+		// repush children
+		while (\count($saveChildren)) {
+			$root->children[] = array_pop($saveChildren);
+		}
+	}
+
+	/**
+	 * Append lines to the current output block:
+	 * directly to the block or through a child if necessary
+	 *
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 * @param string                                 $type
+	 * @param string|mixed                           $line
+	 */
+	protected function appendOutputLine(OutputBlock $out, $type, $line)
+	{
+		$outWrite = &$out;
+
+		// check if it's a flat output or not
+		if (\count($out->children)) {
+			$lastChild = &$out->children[\count($out->children) - 1];
+
+			if (
+				$lastChild->depth === $out->depth &&
+				\is_null($lastChild->selectors) &&
+				! \count($lastChild->children)
+			) {
+				$outWrite = $lastChild;
+			} else {
+				$nextLines = $this->makeOutputBlock($type);
+				$nextLines->parent = $out;
+				$nextLines->depth  = $out->depth;
+
+				$out->children[] = $nextLines;
+				$outWrite = &$nextLines;
+			}
+		}
+
+		$outWrite->lines[] = $line;
+	}
+
+	/**
+	 * Compile child; returns a value to halt execution
+	 *
+	 * @param array                                  $child
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 *
+	 * @return array
+	 */
+	protected function compileChild($child, OutputBlock $out)
+	{
+		if (isset($child[Parser::SOURCE_LINE])) {
+			$this->sourceIndex  = isset($child[Parser::SOURCE_INDEX]) ? $child[Parser::SOURCE_INDEX] : null;
+			$this->sourceLine   = isset($child[Parser::SOURCE_LINE]) ? $child[Parser::SOURCE_LINE] : -1;
+			$this->sourceColumn = isset($child[Parser::SOURCE_COLUMN]) ? $child[Parser::SOURCE_COLUMN] : -1;
+		} elseif (\is_array($child) && isset($child[1]->sourceLine)) {
+			$this->sourceIndex  = $child[1]->sourceIndex;
+			$this->sourceLine   = $child[1]->sourceLine;
+			$this->sourceColumn = $child[1]->sourceColumn;
+		} elseif (! empty($out->sourceLine) && ! empty($out->sourceName)) {
+			$this->sourceLine   = $out->sourceLine;
+			$this->sourceIndex  = array_search($out->sourceName, $this->sourceNames);
+			$this->sourceColumn = $out->sourceColumn;
+
+			if ($this->sourceIndex === false) {
+				$this->sourceIndex = null;
+			}
+		}
+
+		switch ($child[0]) {
+			case Type::T_SCSSPHP_IMPORT_ONCE:
+				$rawPath = $this->reduce($child[1]);
+
+				$this->compileImport($rawPath, $out, true);
+				break;
+
+			case Type::T_IMPORT:
+				$rawPath = $this->reduce($child[1]);
+
+				$this->compileImport($rawPath, $out);
+				break;
+
+			case Type::T_DIRECTIVE:
+				$this->compileDirective($child[1], $out);
+				break;
+
+			case Type::T_AT_ROOT:
+				$this->compileAtRoot($child[1]);
+				break;
+
+			case Type::T_MEDIA:
+				$this->compileMedia($child[1]);
+				break;
+
+			case Type::T_BLOCK:
+				$this->compileBlock($child[1]);
+				break;
+
+			case Type::T_CHARSET:
+				if (! $this->charsetSeen) {
+					$this->charsetSeen = true;
+					$this->appendRootDirective('@charset ' . $this->compileValue($child[1]) . ';', $out);
+				}
+				break;
+
+			case Type::T_CUSTOM_PROPERTY:
+				list(, $name, $value) = $child;
+				$compiledName = $this->compileValue($name);
+
+				// if the value reduces to null from something else then
+				// the property should be discarded
+				if ($value[0] !== Type::T_NULL) {
+					$value = $this->reduce($value);
+
+					if ($value[0] === Type::T_NULL || $value === static::$nullString) {
+						break;
+					}
+				}
+
+				$compiledValue = $this->compileValue($value);
+
+				$line = $this->formatter->customProperty(
+					$compiledName,
+					$compiledValue
+				);
+
+				$this->appendOutputLine($out, Type::T_ASSIGN, $line);
+				break;
+
+			case Type::T_ASSIGN:
+				list(, $name, $value) = $child;
+
+				if ($name[0] === Type::T_VARIABLE) {
+					$flags     = isset($child[3]) ? $child[3] : [];
+					$isDefault = \in_array('!default', $flags);
+					$isGlobal  = \in_array('!global', $flags);
+
+					if ($isGlobal) {
+						$this->set($name[1], $this->reduce($value), false, $this->rootEnv, $value);
+						break;
+					}
+
+					$shouldSet = $isDefault &&
+						(\is_null($result = $this->get($name[1], false)) ||
+						$result === static::$null);
+
+					if (! $isDefault || $shouldSet) {
+						$this->set($name[1], $this->reduce($value), true, null, $value);
+					}
+					break;
+				}
+
+				$compiledName = $this->compileValue($name);
+
+				// handle shorthand syntaxes : size / line-height...
+				if (\in_array($compiledName, ['font', 'grid-row', 'grid-column', 'border-radius'])) {
+					if ($value[0] === Type::T_VARIABLE) {
+						// if the font value comes from variable, the content is already reduced
+						// (i.e., formulas were already calculated), so we need the original unreduced value
+						$value = $this->get($value[1], true, null, true);
+					}
+
+					$shorthandValue=&$value;
+
+					$shorthandDividerNeedsUnit = false;
+					$maxListElements           = null;
+					$maxShorthandDividers      = 1;
+
+					switch ($compiledName) {
+						case 'border-radius':
+							$maxListElements = 4;
+							$shorthandDividerNeedsUnit = true;
+							break;
+					}
+
+					if ($compiledName === 'font' && $value[0] === Type::T_LIST && $value[1] === ',') {
+						// this is the case if more than one font is given: example: "font: 400 1em/1.3 arial,helvetica"
+						// we need to handle the first list element
+						$shorthandValue=&$value[2][0];
+					}
+
+					if ($shorthandValue[0] === Type::T_EXPRESSION && $shorthandValue[1] === '/') {
+						$revert = true;
+
+						if ($shorthandDividerNeedsUnit) {
+							$divider = $shorthandValue[3];
+
+							if (\is_array($divider)) {
+								$divider = $this->reduce($divider, true);
+							}
+
+							if (\intval($divider->dimension) && ! \count($divider->units)) {
+								$revert = false;
+							}
+						}
+
+						if ($revert) {
+							$shorthandValue = $this->expToString($shorthandValue);
+						}
+					} elseif ($shorthandValue[0] === Type::T_LIST) {
+						foreach ($shorthandValue[2] as &$item) {
+							if ($item[0] === Type::T_EXPRESSION && $item[1] === '/') {
+								if ($maxShorthandDividers > 0) {
+									$revert = true;
+
+									// if the list of values is too long, this has to be a shorthand,
+									// otherwise it could be a real division
+									if (\is_null($maxListElements) || \count($shorthandValue[2]) <= $maxListElements) {
+										if ($shorthandDividerNeedsUnit) {
+											$divider = $item[3];
+
+											if (\is_array($divider)) {
+												$divider = $this->reduce($divider, true);
+											}
+
+											if (\intval($divider->dimension) && ! \count($divider->units)) {
+												$revert = false;
+											}
+										}
+									}
+
+									if ($revert) {
+										$item = $this->expToString($item);
+										$maxShorthandDividers--;
+									}
+								}
+							}
+						}
+					}
+				}
+
+				// if the value reduces to null from something else then
+				// the property should be discarded
+				if ($value[0] !== Type::T_NULL) {
+					$value = $this->reduce($value);
+
+					if ($value[0] === Type::T_NULL || $value === static::$nullString) {
+						break;
+					}
+				}
+
+				$compiledValue = $this->compileValue($value);
+
+				// ignore empty value
+				if (\strlen($compiledValue)) {
+					$line = $this->formatter->property(
+						$compiledName,
+						$compiledValue
+					);
+					$this->appendOutputLine($out, Type::T_ASSIGN, $line);
+				}
+				break;
+
+			case Type::T_COMMENT:
+				if ($out->type === Type::T_ROOT) {
+					$this->compileComment($child);
+					break;
+				}
+
+				$line = $this->compileCommentValue($child, true);
+				$this->appendOutputLine($out, Type::T_COMMENT, $line);
+				break;
+
+			case Type::T_MIXIN:
+			case Type::T_FUNCTION:
+				list(, $block) = $child;
+				// the block need to be able to go up to it's parent env to resolve vars
+				$block->parentEnv = $this->getStoreEnv();
+				$this->set(static::$namespaces[$block->type] . $block->name, $block, true);
+				break;
+
+			case Type::T_EXTEND:
+				foreach ($child[1] as $sel) {
+					$sel = $this->replaceSelfSelector($sel);
+					$results = $this->evalSelectors([$sel]);
+
+					foreach ($results as $result) {
+						// only use the first one
+						$result = current($result);
+						$selectors = $out->selectors;
+
+						if (! $selectors && isset($child['selfParent'])) {
+							$selectors = $this->multiplySelectors($this->env, $child['selfParent']);
+						}
+
+						$this->pushExtends($result, $selectors, $child);
+					}
+				}
+				break;
+
+			case Type::T_IF:
+				list(, $if) = $child;
+
+				if ($this->isTruthy($this->reduce($if->cond, true))) {
+					return $this->compileChildren($if->children, $out);
+				}
+
+				foreach ($if->cases as $case) {
+					if (
+						$case->type === Type::T_ELSE ||
+						$case->type === Type::T_ELSEIF && $this->isTruthy($this->reduce($case->cond))
+					) {
+						return $this->compileChildren($case->children, $out);
+					}
+				}
+				break;
+
+			case Type::T_EACH:
+				list(, $each) = $child;
+
+				$list = $this->coerceList($this->reduce($each->list), ',', true);
+
+				$this->pushEnv();
+
+				foreach ($list[2] as $item) {
+					if (\count($each->vars) === 1) {
+						$this->set($each->vars[0], $item, true);
+					} else {
+						list(,, $values) = $this->coerceList($item);
+
+						foreach ($each->vars as $i => $var) {
+							$this->set($var, isset($values[$i]) ? $values[$i] : static::$null, true);
+						}
+					}
+
+					$ret = $this->compileChildren($each->children, $out);
+
+					if ($ret) {
+						if ($ret[0] !== Type::T_CONTROL) {
+							$store = $this->env->store;
+							$this->popEnv();
+							$this->backPropagateEnv($store, $each->vars);
+
+							return $ret;
+						}
+
+						if ($ret[1]) {
+							break;
+						}
+					}
+				}
+				$store = $this->env->store;
+				$this->popEnv();
+				$this->backPropagateEnv($store, $each->vars);
+
+				break;
+
+			case Type::T_WHILE:
+				list(, $while) = $child;
+
+				while ($this->isTruthy($this->reduce($while->cond, true))) {
+					$ret = $this->compileChildren($while->children, $out);
+
+					if ($ret) {
+						if ($ret[0] !== Type::T_CONTROL) {
+							return $ret;
+						}
 
-                        if ($ret[1]) {
-                            break;
-                        }
-                    }
-                }
-                break;
-
-            case Type::T_FOR:
-                list(, $for) = $child;
+						if ($ret[1]) {
+							break;
+						}
+					}
+				}
+				break;
+
+			case Type::T_FOR:
+				list(, $for) = $child;
 
-                $start = $this->reduce($for->start, true);
-                $end   = $this->reduce($for->end, true);
+				$start = $this->reduce($for->start, true);
+				$end   = $this->reduce($for->end, true);
 
-                if (! $start instanceof Node\Number) {
-                    throw $this->error('%s is not a number', $start[0]);
-                }
+				if (! $start instanceof Node\Number) {
+					throw $this->error('%s is not a number', $start[0]);
+				}
 
-                if (! $end instanceof Node\Number) {
-                    throw $this->error('%s is not a number', $end[0]);
-                }
-
-                if (! ($start[2] == $end[2] || $end->unitless())) {
-                    throw $this->error('Incompatible units: "%s" && "%s".', $start->unitStr(), $end->unitStr());
-                }
-
-                $unit  = $start[2];
-                $start = $start[1];
-                $end   = $end[1];
-
-                $d = $start < $end ? 1 : -1;
-
-                $this->pushEnv();
-
-                for (;;) {
-                    if (
-                        (! $for->until && $start - $d == $end) ||
-                        ($for->until && $start == $end)
-                    ) {
-                        break;
-                    }
-
-                    $this->set($for->var, new Node\Number($start, $unit));
-                    $start += $d;
-
-                    $ret = $this->compileChildren($for->children, $out);
-
-                    if ($ret) {
-                        if ($ret[0] !== Type::T_CONTROL) {
-                            $store = $this->env->store;
-                            $this->popEnv();
-                            $this->backPropagateEnv($store, [$for->var]);
+				if (! $end instanceof Node\Number) {
+					throw $this->error('%s is not a number', $end[0]);
+				}
+
+				if (! ($start[2] == $end[2] || $end->unitless())) {
+					throw $this->error('Incompatible units: "%s" && "%s".', $start->unitStr(), $end->unitStr());
+				}
+
+				$unit  = $start[2];
+				$start = $start[1];
+				$end   = $end[1];
+
+				$d = $start < $end ? 1 : -1;
+
+				$this->pushEnv();
+
+				for (;;) {
+					if (
+						(! $for->until && $start - $d == $end) ||
+						($for->until && $start == $end)
+					) {
+						break;
+					}
+
+					$this->set($for->var, new Node\Number($start, $unit));
+					$start += $d;
+
+					$ret = $this->compileChildren($for->children, $out);
+
+					if ($ret) {
+						if ($ret[0] !== Type::T_CONTROL) {
+							$store = $this->env->store;
+							$this->popEnv();
+							$this->backPropagateEnv($store, [$for->var]);
 
-                            return $ret;
-                        }
-
-                        if ($ret[1]) {
-                            break;
-                        }
-                    }
-                }
-
-                $store = $this->env->store;
-                $this->popEnv();
-                $this->backPropagateEnv($store, [$for->var]);
+							return $ret;
+						}
+
+						if ($ret[1]) {
+							break;
+						}
+					}
+				}
+
+				$store = $this->env->store;
+				$this->popEnv();
+				$this->backPropagateEnv($store, [$for->var]);
 
-                break;
+				break;
 
-            case Type::T_BREAK:
-                return [Type::T_CONTROL, true];
-
-            case Type::T_CONTINUE:
-                return [Type::T_CONTROL, false];
-
-            case Type::T_RETURN:
-                return $this->reduce($child[1], true);
-
-            case Type::T_NESTED_PROPERTY:
-                $this->compileNestedPropertiesBlock($child[1], $out);
-                break;
-
-            case Type::T_INCLUDE:
-                // including a mixin
-                list(, $name, $argValues, $content, $argUsing) = $child;
+			case Type::T_BREAK:
+				return [Type::T_CONTROL, true];
+
+			case Type::T_CONTINUE:
+				return [Type::T_CONTROL, false];
+
+			case Type::T_RETURN:
+				return $this->reduce($child[1], true);
+
+			case Type::T_NESTED_PROPERTY:
+				$this->compileNestedPropertiesBlock($child[1], $out);
+				break;
+
+			case Type::T_INCLUDE:
+				// including a mixin
+				list(, $name, $argValues, $content, $argUsing) = $child;
 
-                $mixin = $this->get(static::$namespaces['mixin'] . $name, false);
+				$mixin = $this->get(static::$namespaces['mixin'] . $name, false);
 
-                if (! $mixin) {
-                    throw $this->error("Undefined mixin $name");
-                }
+				if (! $mixin) {
+					throw $this->error("Undefined mixin $name");
+				}
 
-                $callingScope = $this->getStoreEnv();
+				$callingScope = $this->getStoreEnv();
 
-                // push scope, apply args
-                $this->pushEnv();
-                $this->env->depth--;
+				// push scope, apply args
+				$this->pushEnv();
+				$this->env->depth--;
 
-                // Find the parent selectors in the env to be able to know what '&' refers to in the mixin
-                // and assign this fake parent to childs
-                $selfParent = null;
+				// Find the parent selectors in the env to be able to know what '&' refers to in the mixin
+				// and assign this fake parent to childs
+				$selfParent = null;
 
-                if (isset($child['selfParent']) && isset($child['selfParent']->selectors)) {
-                    $selfParent = $child['selfParent'];
-                } else {
-                    $parentSelectors = $this->multiplySelectors($this->env);
+				if (isset($child['selfParent']) && isset($child['selfParent']->selectors)) {
+					$selfParent = $child['selfParent'];
+				} else {
+					$parentSelectors = $this->multiplySelectors($this->env);
 
-                    if ($parentSelectors) {
-                        $parent = new Block();
-                        $parent->selectors = $parentSelectors;
+					if ($parentSelectors) {
+						$parent = new Block();
+						$parent->selectors = $parentSelectors;
 
-                        foreach ($mixin->children as $k => $child) {
-                            if (isset($child[1]) && \is_object($child[1]) && $child[1] instanceof Block) {
-                                $mixin->children[$k][1]->parent = $parent;
-                            }
-                        }
-                    }
-                }
+						foreach ($mixin->children as $k => $child) {
+							if (isset($child[1]) && \is_object($child[1]) && $child[1] instanceof Block) {
+								$mixin->children[$k][1]->parent = $parent;
+							}
+						}
+					}
+				}
 
-                // clone the stored content to not have its scope spoiled by a further call to the same mixin
-                // i.e., recursive @include of the same mixin
-                if (isset($content)) {
-                    $copyContent = clone $content;
-                    $copyContent->scope = clone $callingScope;
+				// clone the stored content to not have its scope spoiled by a further call to the same mixin
+				// i.e., recursive @include of the same mixin
+				if (isset($content)) {
+					$copyContent = clone $content;
+					$copyContent->scope = clone $callingScope;
 
-                    $this->setRaw(static::$namespaces['special'] . 'content', $copyContent, $this->env);
-                } else {
-                    $this->setRaw(static::$namespaces['special'] . 'content', null, $this->env);
-                }
+					$this->setRaw(static::$namespaces['special'] . 'content', $copyContent, $this->env);
+				} else {
+					$this->setRaw(static::$namespaces['special'] . 'content', null, $this->env);
+				}
 
-                // save the "using" argument list for applying it to when "@content" is invoked
-                if (isset($argUsing)) {
-                    $this->setRaw(static::$namespaces['special'] . 'using', $argUsing, $this->env);
-                } else {
-                    $this->setRaw(static::$namespaces['special'] . 'using', null, $this->env);
-                }
+				// save the "using" argument list for applying it to when "@content" is invoked
+				if (isset($argUsing)) {
+					$this->setRaw(static::$namespaces['special'] . 'using', $argUsing, $this->env);
+				} else {
+					$this->setRaw(static::$namespaces['special'] . 'using', null, $this->env);
+				}
 
-                if (isset($mixin->args)) {
-                    $this->applyArguments($mixin->args, $argValues);
-                }
+				if (isset($mixin->args)) {
+					$this->applyArguments($mixin->args, $argValues);
+				}
 
-                $this->env->marker = 'mixin';
+				$this->env->marker = 'mixin';
 
-                if (! empty($mixin->parentEnv)) {
-                    $this->env->declarationScopeParent = $mixin->parentEnv;
-                } else {
-                    throw $this->error("@mixin $name() without parentEnv");
-                }
+				if (! empty($mixin->parentEnv)) {
+					$this->env->declarationScopeParent = $mixin->parentEnv;
+				} else {
+					throw $this->error("@mixin $name() without parentEnv");
+				}
 
-                $this->compileChildrenNoReturn($mixin->children, $out, $selfParent, $this->env->marker . ' ' . $name);
+				$this->compileChildrenNoReturn($mixin->children, $out, $selfParent, $this->env->marker . ' ' . $name);
 
-                $this->popEnv();
-                break;
+				$this->popEnv();
+				break;
 
-            case Type::T_MIXIN_CONTENT:
-                $env        = isset($this->storeEnv) ? $this->storeEnv : $this->env;
-                $content    = $this->get(static::$namespaces['special'] . 'content', false, $env);
-                $argUsing   = $this->get(static::$namespaces['special'] . 'using', false, $env);
-                $argContent = $child[1];
+			case Type::T_MIXIN_CONTENT:
+				$env        = isset($this->storeEnv) ? $this->storeEnv : $this->env;
+				$content    = $this->get(static::$namespaces['special'] . 'content', false, $env);
+				$argUsing   = $this->get(static::$namespaces['special'] . 'using', false, $env);
+				$argContent = $child[1];
 
-                if (! $content) {
-                    break;
-                }
+				if (! $content) {
+					break;
+				}
 
-                $storeEnv = $this->storeEnv;
-                $varsUsing = [];
+				$storeEnv = $this->storeEnv;
+				$varsUsing = [];
 
-                if (isset($argUsing) && isset($argContent)) {
-                    // Get the arguments provided for the content with the names provided in the "using" argument list
-                    $this->storeEnv = null;
-                    $varsUsing = $this->applyArguments($argUsing, $argContent, false);
-                }
-
-                // restore the scope from the @content
-                $this->storeEnv = $content->scope;
-
-                // append the vars from using if any
-                foreach ($varsUsing as $name => $val) {
-                    $this->set($name, $val, true, $this->storeEnv);
-                }
-
-                $this->compileChildrenNoReturn($content->children, $out);
-
-                $this->storeEnv = $storeEnv;
-                break;
-
-            case Type::T_DEBUG:
-                list(, $value) = $child;
-
-                $fname = $this->sourceNames[$this->sourceIndex];
-                $line  = $this->sourceLine;
-                $value = $this->compileDebugValue($value);
-
-                fwrite($this->stderr, "$fname:$line DEBUG: $value\n");
-                break;
-
-            case Type::T_WARN:
-                list(, $value) = $child;
-
-                $fname = $this->sourceNames[$this->sourceIndex];
-                $line  = $this->sourceLine;
-                $value = $this->compileDebugValue($value);
-
-                fwrite($this->stderr, "WARNING: $value\n         on line $line of $fname\n\n");
-                break;
-
-            case Type::T_ERROR:
-                list(, $value) = $child;
-
-                $fname = $this->sourceNames[$this->sourceIndex];
-                $line  = $this->sourceLine;
-                $value = $this->compileValue($this->reduce($value, true));
-
-                throw $this->error("File $fname on line $line ERROR: $value\n");
-
-            case Type::T_CONTROL:
-                throw $this->error('@break/@continue not permitted in this scope');
-
-            default:
-                throw $this->error("unknown child type: $child[0]");
-        }
-    }
-
-    /**
-     * Reduce expression to string
-     *
-     * @param array $exp
-     *
-     * @return array
-     */
-    protected function expToString($exp)
-    {
-        list(, $op, $left, $right, /* $inParens */, $whiteLeft, $whiteRight) = $exp;
-
-        $content = [$this->reduce($left)];
-
-        if ($whiteLeft) {
-            $content[] = ' ';
-        }
-
-        $content[] = $op;
-
-        if ($whiteRight) {
-            $content[] = ' ';
-        }
-
-        $content[] = $this->reduce($right);
-
-        return [Type::T_STRING, '', $content];
-    }
-
-    /**
-     * Is truthy?
-     *
-     * @param array $value
-     *
-     * @return boolean
-     */
-    protected function isTruthy($value)
-    {
-        return $value !== static::$false && $value !== static::$null;
-    }
-
-    /**
-     * Is the value a direct relationship combinator?
-     *
-     * @param string $value
-     *
-     * @return boolean
-     */
-    protected function isImmediateRelationshipCombinator($value)
-    {
-        return $value === '>' || $value === '+' || $value === '~';
-    }
-
-    /**
-     * Should $value cause its operand to eval
-     *
-     * @param array $value
-     *
-     * @return boolean
-     */
-    protected function shouldEval($value)
-    {
-        switch ($value[0]) {
-            case Type::T_EXPRESSION:
-                if ($value[1] === '/') {
-                    return $this->shouldEval($value[2]) || $this->shouldEval($value[3]);
-                }
-
-                // fall-thru
-            case Type::T_VARIABLE:
-            case Type::T_FUNCTION_CALL:
-                return true;
-        }
-
-        return false;
-    }
-
-    /**
-     * Reduce value
-     *
-     * @param array   $value
-     * @param boolean $inExp
-     *
-     * @return null|string|array|\ScssPhp\ScssPhp\Node\Number
-     */
-    protected function reduce($value, $inExp = false)
-    {
-        if (\is_null($value)) {
-            return null;
-        }
-
-        switch ($value[0]) {
-            case Type::T_EXPRESSION:
-                list(, $op, $left, $right, $inParens) = $value;
-
-                $opName = isset(static::$operatorNames[$op]) ? static::$operatorNames[$op] : $op;
-                $inExp = $inExp || $this->shouldEval($left) || $this->shouldEval($right);
-
-                $left = $this->reduce($left, true);
-
-                if ($op !== 'and' && $op !== 'or') {
-                    $right = $this->reduce($right, true);
-                }
-
-                // special case: looks like css shorthand
-                if (
-                    $opName == 'div' && ! $inParens && ! $inExp && isset($right[2]) &&
-                    (($right[0] !== Type::T_NUMBER && $right[2] != '') ||
-                    ($right[0] === Type::T_NUMBER && ! $right->unitless()))
-                ) {
-                    return $this->expToString($value);
-                }
-
-                $left  = $this->coerceForExpression($left);
-                $right = $this->coerceForExpression($right);
-                $ltype = $left[0];
-                $rtype = $right[0];
-
-                $ucOpName = ucfirst($opName);
-                $ucLType  = ucfirst($ltype);
-                $ucRType  = ucfirst($rtype);
-
-                // this tries:
-                // 1. op[op name][left type][right type]
-                // 2. op[left type][right type] (passing the op as first arg
-                // 3. op[op name]
-                $fn = "op${ucOpName}${ucLType}${ucRType}";
-
-                if (
-                    \is_callable([$this, $fn]) ||
-                    (($fn = "op${ucLType}${ucRType}") &&
-                        \is_callable([$this, $fn]) &&
-                        $passOp = true) ||
-                    (($fn = "op${ucOpName}") &&
-                        \is_callable([$this, $fn]) &&
-                        $genOp = true)
-                ) {
-                    $coerceUnit = false;
-
-                    if (
-                        ! isset($genOp) &&
-                        $left[0] === Type::T_NUMBER && $right[0] === Type::T_NUMBER
-                    ) {
-                        $coerceUnit = true;
-
-                        switch ($opName) {
-                            case 'mul':
-                                $targetUnit = $left[2];
-
-                                foreach ($right[2] as $unit => $exp) {
-                                    $targetUnit[$unit] = (isset($targetUnit[$unit]) ? $targetUnit[$unit] : 0) + $exp;
-                                }
-                                break;
-
-                            case 'div':
-                                $targetUnit = $left[2];
-
-                                foreach ($right[2] as $unit => $exp) {
-                                    $targetUnit[$unit] = (isset($targetUnit[$unit]) ? $targetUnit[$unit] : 0) - $exp;
-                                }
-                                break;
-
-                            case 'mod':
-                                $targetUnit = $left[2];
-                                break;
-
-                            default:
-                                $targetUnit = $left->unitless() ? $right[2] : $left[2];
-                        }
-
-                        $baseUnitLeft = $left->isNormalizable();
-                        $baseUnitRight = $right->isNormalizable();
-
-                        if ($baseUnitLeft && $baseUnitRight && $baseUnitLeft === $baseUnitRight) {
-                            $left = $left->normalize();
-                            $right = $right->normalize();
-                        } elseif ($coerceUnit) {
-                            $left = new Node\Number($left[1], []);
-                        }
-                    }
-
-                    $shouldEval = $inParens || $inExp;
-
-                    if (isset($passOp)) {
-                        $out = $this->$fn($op, $left, $right, $shouldEval);
-                    } else {
-                        $out = $this->$fn($left, $right, $shouldEval);
-                    }
-
-                    if (isset($out)) {
-                        if ($coerceUnit && $out[0] === Type::T_NUMBER) {
-                            $out = $out->coerce($targetUnit);
-                        }
-
-                        return $out;
-                    }
-                }
-
-                return $this->expToString($value);
-
-            case Type::T_UNARY:
-                list(, $op, $exp, $inParens) = $value;
-
-                $inExp = $inExp || $this->shouldEval($exp);
-                $exp = $this->reduce($exp);
-
-                if ($exp[0] === Type::T_NUMBER) {
-                    switch ($op) {
-                        case '+':
-                            return new Node\Number($exp[1], $exp[2]);
-
-                        case '-':
-                            return new Node\Number(-$exp[1], $exp[2]);
-                    }
-                }
-
-                if ($op === 'not') {
-                    if ($inExp || $inParens) {
-                        if ($exp === static::$false || $exp === static::$null) {
-                            return static::$true;
-                        }
-
-                        return static::$false;
-                    }
-
-                    $op = $op . ' ';
-                }
-
-                return [Type::T_STRING, '', [$op, $exp]];
-
-            case Type::T_VARIABLE:
-                return $this->reduce($this->get($value[1]));
-
-            case Type::T_LIST:
-                foreach ($value[2] as &$item) {
-                    $item = $this->reduce($item);
-                }
-
-                return $value;
-
-            case Type::T_MAP:
-                foreach ($value[1] as &$item) {
-                    $item = $this->reduce($item);
-                }
-
-                foreach ($value[2] as &$item) {
-                    $item = $this->reduce($item);
-                }
-
-                return $value;
-
-            case Type::T_STRING:
-                foreach ($value[2] as &$item) {
-                    if (\is_array($item) || $item instanceof \ArrayAccess) {
-                        $item = $this->reduce($item);
-                    }
-                }
-
-                return $value;
-
-            case Type::T_INTERPOLATE:
-                $value[1] = $this->reduce($value[1]);
-
-                if ($inExp) {
-                    return $value[1];
-                }
-
-                return $value;
-
-            case Type::T_FUNCTION_CALL:
-                return $this->fncall($value[1], $value[2]);
-
-            case Type::T_SELF:
-                $selfParent = ! empty($this->env->block->selfParent) ? $this->env->block->selfParent : null;
-                $selfSelector = $this->multiplySelectors($this->env, $selfParent);
-                $selfSelector = $this->collapseSelectors($selfSelector, true);
-
-                return $selfSelector;
-
-            default:
-                return $value;
-        }
-    }
-
-    /**
-     * Function caller
-     *
-     * @param string $name
-     * @param array  $argValues
-     *
-     * @return array|null
-     */
-    protected function fncall($functionReference, $argValues)
-    {
-        // a string means this is a static hard reference coming from the parsing
-        if (is_string($functionReference)) {
-            $name = $functionReference;
-
-            $functionReference = $this->getFunctionReference($name);
-            if ($functionReference === static::$null || $functionReference[0] !== Type::T_FUNCTION_REFERENCE) {
-                $functionReference = [Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]];
-            }
-        }
-
-        // a function type means we just want a plain css function call
-        if ($functionReference[0] === Type::T_FUNCTION) {
-            // for CSS functions, simply flatten the arguments into a list
-            $listArgs = [];
-
-            foreach ((array) $argValues as $arg) {
-                if (empty($arg[0]) || count($argValues) === 1) {
-                    $listArgs[] = $this->reduce($this->stringifyFncallArgs($arg[1]));
-                }
-            }
-
-            return [Type::T_FUNCTION, $functionReference[1], [Type::T_LIST, ',', $listArgs]];
-        }
-
-        if ($functionReference === static::$null || $functionReference[0] !== Type::T_FUNCTION_REFERENCE) {
-            return static::$defaultValue;
-        }
-
-
-        switch ($functionReference[1]) {
-            // SCSS @function
-            case 'scss':
-                return $this->callScssFunction($functionReference[3], $argValues);
-
-            // native PHP functions
-            case 'user':
-            case 'native':
-                list(,,$name, $fn, $prototype) = $functionReference;
-                $returnValue = $this->callNativeFunction($name, $fn, $prototype, $argValues);
-
-                if (! isset($returnValue)) {
-                    return $this->fncall([Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]], $argValues);
-                }
-
-                return $returnValue;
-
-            default:
-                return static::$defaultValue;
-        }
-    }
-
-    /**
-     * Reformat fncall arguments to proper css function output
-     * @param $arg
-     * @return array|\ArrayAccess|Node\Number|string|null
-     */
-    protected function stringifyFncallArgs($arg)
-    {
-
-        switch ($arg[0]) {
-            case Type::T_LIST:
-                foreach ($arg[2] as $k => $v) {
-                    $arg[2][$k] = $this->stringifyFncallArgs($v);
-                }
-                break;
-
-            case Type::T_EXPRESSION:
-                if ($arg[1] === '/') {
-                    $arg[2] = $this->stringifyFncallArgs($arg[2]);
-                    $arg[3] = $this->stringifyFncallArgs($arg[3]);
-                    $arg[5] = $arg[6] = false; // no space around /
-                    $arg = $this->expToString($arg);
-                }
-                break;
-
-            case Type::T_FUNCTION_CALL:
-                $name = $arg[1];
-
-                if (in_array($name, ['max', 'min', 'calc'])) {
-                    $args = $arg[2];
-                    $arg = $this->fncall([Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]], $args);
-                }
-                break;
-        }
-
-        return $arg;
-    }
-
-    /**
-     * Find a function reference
-     * @param string $name
-     * @param bool $safeCopy
-     * @return array
-     */
-    protected function getFunctionReference($name, $safeCopy = false)
-    {
-        // SCSS @function
-        if ($func = $this->get(static::$namespaces['function'] . $name, false)) {
-            if ($safeCopy) {
-                $func = clone $func;
-            }
-
-            return [Type::T_FUNCTION_REFERENCE, 'scss', $name, $func];
-        }
-
-        // native PHP functions
-
-        // try to find a native lib function
-        $normalizedName = $this->normalizeName($name);
-        $libName = null;
-
-        if (isset($this->userFunctions[$normalizedName])) {
-            // see if we can find a user function
-            list($f, $prototype) = $this->userFunctions[$normalizedName];
-
-            return [Type::T_FUNCTION_REFERENCE, 'user', $name, $f, $prototype];
-        }
-
-        if (($f = $this->getBuiltinFunction($normalizedName)) && \is_callable($f)) {
-            $libName   = $f[1];
-            $prototype = isset(static::$$libName) ? static::$$libName : null;
-
-            return [Type::T_FUNCTION_REFERENCE, 'native', $name, $f, $prototype];
-        }
-
-        return static::$null;
-    }
-
-
-    /**
-     * Normalize name
-     *
-     * @param string $name
-     *
-     * @return string
-     */
-    protected function normalizeName($name)
-    {
-        return str_replace('-', '_', $name);
-    }
-
-    /**
-     * Normalize value
-     *
-     * @param array $value
-     *
-     * @return array
-     */
-    public function normalizeValue($value)
-    {
-        $value = $this->coerceForExpression($this->reduce($value));
-
-        switch ($value[0]) {
-            case Type::T_LIST:
-                $value = $this->extractInterpolation($value);
-
-                if ($value[0] !== Type::T_LIST) {
-                    return [Type::T_KEYWORD, $this->compileValue($value)];
-                }
-
-                foreach ($value[2] as $key => $item) {
-                    $value[2][$key] = $this->normalizeValue($item);
-                }
-
-                if (! empty($value['enclosing'])) {
-                    unset($value['enclosing']);
-                }
-
-                return $value;
-
-            case Type::T_STRING:
-                return [$value[0], '"', [$this->compileStringContent($value)]];
-
-            case Type::T_NUMBER:
-                return $value->normalize();
-
-            case Type::T_INTERPOLATE:
-                return [Type::T_KEYWORD, $this->compileValue($value)];
-
-            default:
-                return $value;
-        }
-    }
-
-    /**
-     * Add numbers
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return \ScssPhp\ScssPhp\Node\Number
-     */
-    protected function opAddNumberNumber($left, $right)
-    {
-        return new Node\Number($left[1] + $right[1], $left[2]);
-    }
-
-    /**
-     * Multiply numbers
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return \ScssPhp\ScssPhp\Node\Number
-     */
-    protected function opMulNumberNumber($left, $right)
-    {
-        return new Node\Number($left[1] * $right[1], $left[2]);
-    }
-
-    /**
-     * Subtract numbers
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return \ScssPhp\ScssPhp\Node\Number
-     */
-    protected function opSubNumberNumber($left, $right)
-    {
-        return new Node\Number($left[1] - $right[1], $left[2]);
-    }
-
-    /**
-     * Divide numbers
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array|\ScssPhp\ScssPhp\Node\Number
-     */
-    protected function opDivNumberNumber($left, $right)
-    {
-        if ($right[1] == 0) {
-            return ($left[1] == 0) ? static::$NaN : static::$Infinity;
-        }
-
-        return new Node\Number($left[1] / $right[1], $left[2]);
-    }
-
-    /**
-     * Mod numbers
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return \ScssPhp\ScssPhp\Node\Number
-     */
-    protected function opModNumberNumber($left, $right)
-    {
-        if ($right[1] == 0) {
-            return static::$NaN;
-        }
-
-        return new Node\Number($left[1] % $right[1], $left[2]);
-    }
-
-    /**
-     * Add strings
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array|null
-     */
-    protected function opAdd($left, $right)
-    {
-        if ($strLeft = $this->coerceString($left)) {
-            if ($right[0] === Type::T_STRING) {
-                $right[1] = '';
-            }
-
-            $strLeft[2][] = $right;
-
-            return $strLeft;
-        }
-
-        if ($strRight = $this->coerceString($right)) {
-            if ($left[0] === Type::T_STRING) {
-                $left[1] = '';
-            }
-
-            array_unshift($strRight[2], $left);
-
-            return $strRight;
-        }
-
-        return null;
-    }
-
-    /**
-     * Boolean and
-     *
-     * @param array   $left
-     * @param array   $right
-     * @param boolean $shouldEval
-     *
-     * @return array|null
-     */
-    protected function opAnd($left, $right, $shouldEval)
-    {
-        $truthy = ($left === static::$null || $right === static::$null) ||
-                  ($left === static::$false || $left === static::$true) &&
-                  ($right === static::$false || $right === static::$true);
-
-        if (! $shouldEval) {
-            if (! $truthy) {
-                return null;
-            }
-        }
-
-        if ($left !== static::$false && $left !== static::$null) {
-            return $this->reduce($right, true);
-        }
-
-        return $left;
-    }
-
-    /**
-     * Boolean or
-     *
-     * @param array   $left
-     * @param array   $right
-     * @param boolean $shouldEval
-     *
-     * @return array|null
-     */
-    protected function opOr($left, $right, $shouldEval)
-    {
-        $truthy = ($left === static::$null || $right === static::$null) ||
-                  ($left === static::$false || $left === static::$true) &&
-                  ($right === static::$false || $right === static::$true);
-
-        if (! $shouldEval) {
-            if (! $truthy) {
-                return null;
-            }
-        }
-
-        if ($left !== static::$false && $left !== static::$null) {
-            return $left;
-        }
-
-        return $this->reduce($right, true);
-    }
-
-    /**
-     * Compare colors
-     *
-     * @param string $op
-     * @param array  $left
-     * @param array  $right
-     *
-     * @return array
-     */
-    protected function opColorColor($op, $left, $right)
-    {
-        $out = [Type::T_COLOR];
-
-        foreach ([1, 2, 3] as $i) {
-            $lval = isset($left[$i]) ? $left[$i] : 0;
-            $rval = isset($right[$i]) ? $right[$i] : 0;
-
-            switch ($op) {
-                case '+':
-                    $out[] = $lval + $rval;
-                    break;
-
-                case '-':
-                    $out[] = $lval - $rval;
-                    break;
-
-                case '*':
-                    $out[] = $lval * $rval;
-                    break;
-
-                case '%':
-                    if ($rval == 0) {
-                        throw $this->error("color: Can't take modulo by zero");
-                    }
-
-                    $out[] = $lval % $rval;
-                    break;
-
-                case '/':
-                    if ($rval == 0) {
-                        throw $this->error("color: Can't divide by zero");
-                    }
-
-                    $out[] = (int) ($lval / $rval);
-                    break;
-
-                case '==':
-                    return $this->opEq($left, $right);
-
-                case '!=':
-                    return $this->opNeq($left, $right);
-
-                default:
-                    throw $this->error("color: unknown op $op");
-            }
-        }
-
-        if (isset($left[4])) {
-            $out[4] = $left[4];
-        } elseif (isset($right[4])) {
-            $out[4] = $right[4];
-        }
-
-        return $this->fixColor($out);
-    }
-
-    /**
-     * Compare color and number
-     *
-     * @param string $op
-     * @param array  $left
-     * @param array  $right
-     *
-     * @return array
-     */
-    protected function opColorNumber($op, $left, $right)
-    {
-        $value = $right[1];
-
-        return $this->opColorColor(
-            $op,
-            $left,
-            [Type::T_COLOR, $value, $value, $value]
-        );
-    }
-
-    /**
-     * Compare number and color
-     *
-     * @param string $op
-     * @param array  $left
-     * @param array  $right
-     *
-     * @return array
-     */
-    protected function opNumberColor($op, $left, $right)
-    {
-        $value = $left[1];
-
-        return $this->opColorColor(
-            $op,
-            [Type::T_COLOR, $value, $value, $value],
-            $right
-        );
-    }
-
-    /**
-     * Compare number1 == number2
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array
-     */
-    protected function opEq($left, $right)
-    {
-        if (($lStr = $this->coerceString($left)) && ($rStr = $this->coerceString($right))) {
-            $lStr[1] = '';
-            $rStr[1] = '';
-
-            $left = $this->compileValue($lStr);
-            $right = $this->compileValue($rStr);
-        }
-
-        return $this->toBool($left === $right);
-    }
-
-    /**
-     * Compare number1 != number2
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array
-     */
-    protected function opNeq($left, $right)
-    {
-        if (($lStr = $this->coerceString($left)) && ($rStr = $this->coerceString($right))) {
-            $lStr[1] = '';
-            $rStr[1] = '';
-
-            $left = $this->compileValue($lStr);
-            $right = $this->compileValue($rStr);
-        }
-
-        return $this->toBool($left !== $right);
-    }
-
-    /**
-     * Compare number1 >= number2
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array
-     */
-    protected function opGteNumberNumber($left, $right)
-    {
-        return $this->toBool($left[1] >= $right[1]);
-    }
-
-    /**
-     * Compare number1 > number2
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array
-     */
-    protected function opGtNumberNumber($left, $right)
-    {
-        return $this->toBool($left[1] > $right[1]);
-    }
-
-    /**
-     * Compare number1 <= number2
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array
-     */
-    protected function opLteNumberNumber($left, $right)
-    {
-        return $this->toBool($left[1] <= $right[1]);
-    }
-
-    /**
-     * Compare number1 < number2
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return array
-     */
-    protected function opLtNumberNumber($left, $right)
-    {
-        return $this->toBool($left[1] < $right[1]);
-    }
-
-    /**
-     * Three-way comparison, aka spaceship operator
-     *
-     * @param array $left
-     * @param array $right
-     *
-     * @return \ScssPhp\ScssPhp\Node\Number
-     */
-    protected function opCmpNumberNumber($left, $right)
-    {
-        $n = $left[1] - $right[1];
-
-        return new Node\Number($n ? $n / abs($n) : 0, '');
-    }
-
-    /**
-     * Cast to boolean
-     *
-     * @api
-     *
-     * @param mixed $thing
-     *
-     * @return array
-     */
-    public function toBool($thing)
-    {
-        return $thing ? static::$true : static::$false;
-    }
-
-    /**
-     * Compiles a primitive value into a CSS property value.
-     *
-     * Values in scssphp are typed by being wrapped in arrays, their format is
-     * typically:
-     *
-     *     array(type, contents [, additional_contents]*)
-     *
-     * The input is expected to be reduced. This function will not work on
-     * things like expressions and variables.
-     *
-     * @api
-     *
-     * @param array $value
-     *
-     * @return string|array
-     */
-    public function compileValue($value)
-    {
-        $value = $this->reduce($value);
-
-        switch ($value[0]) {
-            case Type::T_KEYWORD:
-                return $value[1];
-
-            case Type::T_COLOR:
-                // [1] - red component (either number for a %)
-                // [2] - green component
-                // [3] - blue component
-                // [4] - optional alpha component
-                list(, $r, $g, $b) = $value;
-
-                $r = $this->compileRGBAValue($r);
-                $g = $this->compileRGBAValue($g);
-                $b = $this->compileRGBAValue($b);
-
-                if (\count($value) === 5) {
-                    $alpha = $this->compileRGBAValue($value[4], true);
-
-                    if (! is_numeric($alpha) || $alpha < 1) {
-                        $colorName = Colors::RGBaToColorName($r, $g, $b, $alpha);
-
-                        if (! \is_null($colorName)) {
-                            return $colorName;
-                        }
-
-                        if (is_numeric($alpha)) {
-                            $a = new Node\Number($alpha, '');
-                        } else {
-                            $a = $alpha;
-                        }
-
-                        return 'rgba(' . $r . ', ' . $g . ', ' . $b . ', ' . $a . ')';
-                    }
-                }
-
-                if (! is_numeric($r) || ! is_numeric($g) || ! is_numeric($b)) {
-                    return 'rgb(' . $r . ', ' . $g . ', ' . $b . ')';
-                }
-
-                $colorName = Colors::RGBaToColorName($r, $g, $b);
-
-                if (! \is_null($colorName)) {
-                    return $colorName;
-                }
-
-                $h = sprintf('#%02x%02x%02x', $r, $g, $b);
-
-                // Converting hex color to short notation (e.g. #003399 to #039)
-                if ($h[1] === $h[2] && $h[3] === $h[4] && $h[5] === $h[6]) {
-                    $h = '#' . $h[1] . $h[3] . $h[5];
-                }
-
-                return $h;
-
-            case Type::T_NUMBER:
-                return $value->output($this);
-
-            case Type::T_STRING:
-                $content = $this->compileStringContent($value);
-
-                if ($value[1]) {
-                    // force double quote as string quote for the output in certain cases
-                    if (
-                        $value[1] === "'" &&
-                        strpos($content, '"') === false &&
-                        strpbrk($content, '{}') !== false
-                    ) {
-                        $value[1] = '"';
-                    }
-                    $content = str_replace(
-                        array('\\a', "\n", "\f" , '\\'  , "\r" , $value[1]),
-                        array("\r" , ' ' , '\\f', '\\\\', '\\a', '\\' . $value[1]),
-                        $content
-                    );
-                }
-
-                return $value[1] . $content . $value[1];
-
-            case Type::T_FUNCTION:
-                $args = ! empty($value[2]) ? $this->compileValue($value[2]) : '';
-
-                return "$value[1]($args)";
-
-            case Type::T_FUNCTION_REFERENCE:
-                $name = ! empty($value[2]) ? $value[2] : '';
-
-                return "get-function(\"$name\")";
-
-            case Type::T_LIST:
-                $value = $this->extractInterpolation($value);
-
-                if ($value[0] !== Type::T_LIST) {
-                    return $this->compileValue($value);
-                }
+				if (isset($argUsing) && isset($argContent)) {
+					// Get the arguments provided for the content with the names provided in the "using" argument list
+					$this->storeEnv = null;
+					$varsUsing = $this->applyArguments($argUsing, $argContent, false);
+				}
+
+				// restore the scope from the @content
+				$this->storeEnv = $content->scope;
+
+				// append the vars from using if any
+				foreach ($varsUsing as $name => $val) {
+					$this->set($name, $val, true, $this->storeEnv);
+				}
+
+				$this->compileChildrenNoReturn($content->children, $out);
+
+				$this->storeEnv = $storeEnv;
+				break;
+
+			case Type::T_DEBUG:
+				list(, $value) = $child;
+
+				$fname = $this->sourceNames[$this->sourceIndex];
+				$line  = $this->sourceLine;
+				$value = $this->compileDebugValue($value);
+
+				fwrite($this->stderr, "$fname:$line DEBUG: $value\n");
+				break;
+
+			case Type::T_WARN:
+				list(, $value) = $child;
+
+				$fname = $this->sourceNames[$this->sourceIndex];
+				$line  = $this->sourceLine;
+				$value = $this->compileDebugValue($value);
+
+				fwrite($this->stderr, "WARNING: $value\n         on line $line of $fname\n\n");
+				break;
+
+			case Type::T_ERROR:
+				list(, $value) = $child;
+
+				$fname = $this->sourceNames[$this->sourceIndex];
+				$line  = $this->sourceLine;
+				$value = $this->compileValue($this->reduce($value, true));
+
+				throw $this->error("File $fname on line $line ERROR: $value\n");
+
+			case Type::T_CONTROL:
+				throw $this->error('@break/@continue not permitted in this scope');
+
+			default:
+				throw $this->error("unknown child type: $child[0]");
+		}
+	}
+
+	/**
+	 * Reduce expression to string
+	 *
+	 * @param array $exp
+	 *
+	 * @return array
+	 */
+	protected function expToString($exp)
+	{
+		list(, $op, $left, $right, /* $inParens */, $whiteLeft, $whiteRight) = $exp;
+
+		$content = [$this->reduce($left)];
+
+		if ($whiteLeft) {
+			$content[] = ' ';
+		}
+
+		$content[] = $op;
+
+		if ($whiteRight) {
+			$content[] = ' ';
+		}
+
+		$content[] = $this->reduce($right);
+
+		return [Type::T_STRING, '', $content];
+	}
+
+	/**
+	 * Is truthy?
+	 *
+	 * @param array $value
+	 *
+	 * @return boolean
+	 */
+	protected function isTruthy($value)
+	{
+		return $value !== static::$false && $value !== static::$null;
+	}
+
+	/**
+	 * Is the value a direct relationship combinator?
+	 *
+	 * @param string $value
+	 *
+	 * @return boolean
+	 */
+	protected function isImmediateRelationshipCombinator($value)
+	{
+		return $value === '>' || $value === '+' || $value === '~';
+	}
+
+	/**
+	 * Should $value cause its operand to eval
+	 *
+	 * @param array $value
+	 *
+	 * @return boolean
+	 */
+	protected function shouldEval($value)
+	{
+		switch ($value[0]) {
+			case Type::T_EXPRESSION:
+				if ($value[1] === '/') {
+					return $this->shouldEval($value[2]) || $this->shouldEval($value[3]);
+				}
+
+				// fall-thru
+			case Type::T_VARIABLE:
+			case Type::T_FUNCTION_CALL:
+				return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Reduce value
+	 *
+	 * @param array   $value
+	 * @param boolean $inExp
+	 *
+	 * @return null|string|array|\ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function reduce($value, $inExp = false)
+	{
+		if (\is_null($value)) {
+			return null;
+		}
+
+		switch ($value[0]) {
+			case Type::T_EXPRESSION:
+				list(, $op, $left, $right, $inParens) = $value;
+
+				$opName = isset(static::$operatorNames[$op]) ? static::$operatorNames[$op] : $op;
+				$inExp = $inExp || $this->shouldEval($left) || $this->shouldEval($right);
+
+				$left = $this->reduce($left, true);
+
+				if ($op !== 'and' && $op !== 'or') {
+					$right = $this->reduce($right, true);
+				}
+
+				// special case: looks like css shorthand
+				if (
+					$opName == 'div' && ! $inParens && ! $inExp && isset($right[2]) &&
+					(($right[0] !== Type::T_NUMBER && $right[2] != '') ||
+					($right[0] === Type::T_NUMBER && ! $right->unitless()))
+				) {
+					return $this->expToString($value);
+				}
+
+				$left  = $this->coerceForExpression($left);
+				$right = $this->coerceForExpression($right);
+				$ltype = $left[0];
+				$rtype = $right[0];
+
+				$ucOpName = ucfirst($opName);
+				$ucLType  = ucfirst($ltype);
+				$ucRType  = ucfirst($rtype);
+
+				// this tries:
+				// 1. op[op name][left type][right type]
+				// 2. op[left type][right type] (passing the op as first arg
+				// 3. op[op name]
+				$fn = "op${ucOpName}${ucLType}${ucRType}";
+
+				if (
+					\is_callable([$this, $fn]) ||
+					(($fn = "op${ucLType}${ucRType}") &&
+						\is_callable([$this, $fn]) &&
+						$passOp = true) ||
+					(($fn = "op${ucOpName}") &&
+						\is_callable([$this, $fn]) &&
+						$genOp = true)
+				) {
+					$coerceUnit = false;
+
+					if (
+						! isset($genOp) &&
+						$left[0] === Type::T_NUMBER && $right[0] === Type::T_NUMBER
+					) {
+						$coerceUnit = true;
+
+						switch ($opName) {
+							case 'mul':
+								$targetUnit = $left[2];
+
+								foreach ($right[2] as $unit => $exp) {
+									$targetUnit[$unit] = (isset($targetUnit[$unit]) ? $targetUnit[$unit] : 0) + $exp;
+								}
+								break;
+
+							case 'div':
+								$targetUnit = $left[2];
+
+								foreach ($right[2] as $unit => $exp) {
+									$targetUnit[$unit] = (isset($targetUnit[$unit]) ? $targetUnit[$unit] : 0) - $exp;
+								}
+								break;
+
+							case 'mod':
+								$targetUnit = $left[2];
+								break;
+
+							default:
+								$targetUnit = $left->unitless() ? $right[2] : $left[2];
+						}
+
+						$baseUnitLeft = $left->isNormalizable();
+						$baseUnitRight = $right->isNormalizable();
+
+						if ($baseUnitLeft && $baseUnitRight && $baseUnitLeft === $baseUnitRight) {
+							$left = $left->normalize();
+							$right = $right->normalize();
+						} elseif ($coerceUnit) {
+							$left = new Node\Number($left[1], []);
+						}
+					}
+
+					$shouldEval = $inParens || $inExp;
+
+					if (isset($passOp)) {
+						$out = $this->$fn($op, $left, $right, $shouldEval);
+					} else {
+						$out = $this->$fn($left, $right, $shouldEval);
+					}
+
+					if (isset($out)) {
+						if ($coerceUnit && $out[0] === Type::T_NUMBER) {
+							$out = $out->coerce($targetUnit);
+						}
+
+						return $out;
+					}
+				}
+
+				return $this->expToString($value);
+
+			case Type::T_UNARY:
+				list(, $op, $exp, $inParens) = $value;
+
+				$inExp = $inExp || $this->shouldEval($exp);
+				$exp = $this->reduce($exp);
+
+				if ($exp[0] === Type::T_NUMBER) {
+					switch ($op) {
+						case '+':
+							return new Node\Number($exp[1], $exp[2]);
+
+						case '-':
+							return new Node\Number(-$exp[1], $exp[2]);
+					}
+				}
+
+				if ($op === 'not') {
+					if ($inExp || $inParens) {
+						if ($exp === static::$false || $exp === static::$null) {
+							return static::$true;
+						}
+
+						return static::$false;
+					}
+
+					$op = $op . ' ';
+				}
+
+				return [Type::T_STRING, '', [$op, $exp]];
+
+			case Type::T_VARIABLE:
+				return $this->reduce($this->get($value[1]));
+
+			case Type::T_LIST:
+				foreach ($value[2] as &$item) {
+					$item = $this->reduce($item);
+				}
+
+				return $value;
+
+			case Type::T_MAP:
+				foreach ($value[1] as &$item) {
+					$item = $this->reduce($item);
+				}
+
+				foreach ($value[2] as &$item) {
+					$item = $this->reduce($item);
+				}
+
+				return $value;
+
+			case Type::T_STRING:
+				foreach ($value[2] as &$item) {
+					if (\is_array($item) || $item instanceof \ArrayAccess) {
+						$item = $this->reduce($item);
+					}
+				}
+
+				return $value;
+
+			case Type::T_INTERPOLATE:
+				$value[1] = $this->reduce($value[1]);
+
+				if ($inExp) {
+					return $value[1];
+				}
+
+				return $value;
+
+			case Type::T_FUNCTION_CALL:
+				return $this->fncall($value[1], $value[2]);
+
+			case Type::T_SELF:
+				$selfParent = ! empty($this->env->block->selfParent) ? $this->env->block->selfParent : null;
+				$selfSelector = $this->multiplySelectors($this->env, $selfParent);
+				$selfSelector = $this->collapseSelectors($selfSelector, true);
+
+				return $selfSelector;
+
+			default:
+				return $value;
+		}
+	}
+
+	/**
+	 * Function caller
+	 *
+	 * @param string $name
+	 * @param array  $argValues
+	 *
+	 * @return array|null
+	 */
+	protected function fncall($functionReference, $argValues)
+	{
+		// a string means this is a static hard reference coming from the parsing
+		if (is_string($functionReference)) {
+			$name = $functionReference;
+
+			$functionReference = $this->getFunctionReference($name);
+			if ($functionReference === static::$null || $functionReference[0] !== Type::T_FUNCTION_REFERENCE) {
+				$functionReference = [Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]];
+			}
+		}
+
+		// a function type means we just want a plain css function call
+		if ($functionReference[0] === Type::T_FUNCTION) {
+			// for CSS functions, simply flatten the arguments into a list
+			$listArgs = [];
+
+			foreach ((array) $argValues as $arg) {
+				if (empty($arg[0]) || count($argValues) === 1) {
+					$listArgs[] = $this->reduce($this->stringifyFncallArgs($arg[1]));
+				}
+			}
+
+			return [Type::T_FUNCTION, $functionReference[1], [Type::T_LIST, ',', $listArgs]];
+		}
+
+		if ($functionReference === static::$null || $functionReference[0] !== Type::T_FUNCTION_REFERENCE) {
+			return static::$defaultValue;
+		}
+
+
+		switch ($functionReference[1]) {
+			// SCSS @function
+			case 'scss':
+				return $this->callScssFunction($functionReference[3], $argValues);
+
+			// native PHP functions
+			case 'user':
+			case 'native':
+				list(,,$name, $fn, $prototype) = $functionReference;
+				$returnValue = $this->callNativeFunction($name, $fn, $prototype, $argValues);
+
+				if (! isset($returnValue)) {
+					return $this->fncall([Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]], $argValues);
+				}
+
+				return $returnValue;
+
+			default:
+				return static::$defaultValue;
+		}
+	}
+
+	/**
+	 * Reformat fncall arguments to proper css function output
+	 * @param $arg
+	 * @return array|\ArrayAccess|Node\Number|string|null
+	 */
+	protected function stringifyFncallArgs($arg)
+	{
+
+		switch ($arg[0]) {
+			case Type::T_LIST:
+				foreach ($arg[2] as $k => $v) {
+					$arg[2][$k] = $this->stringifyFncallArgs($v);
+				}
+				break;
+
+			case Type::T_EXPRESSION:
+				if ($arg[1] === '/') {
+					$arg[2] = $this->stringifyFncallArgs($arg[2]);
+					$arg[3] = $this->stringifyFncallArgs($arg[3]);
+					$arg[5] = $arg[6] = false; // no space around /
+					$arg = $this->expToString($arg);
+				}
+				break;
+
+			case Type::T_FUNCTION_CALL:
+				$name = $arg[1];
+
+				if (in_array($name, ['max', 'min', 'calc'])) {
+					$args = $arg[2];
+					$arg = $this->fncall([Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]], $args);
+				}
+				break;
+		}
+
+		return $arg;
+	}
+
+	/**
+	 * Find a function reference
+	 * @param string $name
+	 * @param bool $safeCopy
+	 * @return array
+	 */
+	protected function getFunctionReference($name, $safeCopy = false)
+	{
+		// SCSS @function
+		if ($func = $this->get(static::$namespaces['function'] . $name, false)) {
+			if ($safeCopy) {
+				$func = clone $func;
+			}
+
+			return [Type::T_FUNCTION_REFERENCE, 'scss', $name, $func];
+		}
+
+		// native PHP functions
+
+		// try to find a native lib function
+		$normalizedName = $this->normalizeName($name);
+		$libName = null;
+
+		if (isset($this->userFunctions[$normalizedName])) {
+			// see if we can find a user function
+			list($f, $prototype) = $this->userFunctions[$normalizedName];
+
+			return [Type::T_FUNCTION_REFERENCE, 'user', $name, $f, $prototype];
+		}
+
+		if (($f = $this->getBuiltinFunction($normalizedName)) && \is_callable($f)) {
+			$libName   = $f[1];
+			$prototype = isset(static::$$libName) ? static::$$libName : null;
+
+			return [Type::T_FUNCTION_REFERENCE, 'native', $name, $f, $prototype];
+		}
+
+		return static::$null;
+	}
+
+
+	/**
+	 * Normalize name
+	 *
+	 * @param string $name
+	 *
+	 * @return string
+	 */
+	protected function normalizeName($name)
+	{
+		return str_replace('-', '_', $name);
+	}
+
+	/**
+	 * Normalize value
+	 *
+	 * @param array $value
+	 *
+	 * @return array
+	 */
+	public function normalizeValue($value)
+	{
+		$value = $this->coerceForExpression($this->reduce($value));
+
+		switch ($value[0]) {
+			case Type::T_LIST:
+				$value = $this->extractInterpolation($value);
+
+				if ($value[0] !== Type::T_LIST) {
+					return [Type::T_KEYWORD, $this->compileValue($value)];
+				}
+
+				foreach ($value[2] as $key => $item) {
+					$value[2][$key] = $this->normalizeValue($item);
+				}
+
+				if (! empty($value['enclosing'])) {
+					unset($value['enclosing']);
+				}
+
+				return $value;
+
+			case Type::T_STRING:
+				return [$value[0], '"', [$this->compileStringContent($value)]];
+
+			case Type::T_NUMBER:
+				return $value->normalize();
+
+			case Type::T_INTERPOLATE:
+				return [Type::T_KEYWORD, $this->compileValue($value)];
+
+			default:
+				return $value;
+		}
+	}
+
+	/**
+	 * Add numbers
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return \ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function opAddNumberNumber($left, $right)
+	{
+		return new Node\Number($left[1] + $right[1], $left[2]);
+	}
+
+	/**
+	 * Multiply numbers
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return \ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function opMulNumberNumber($left, $right)
+	{
+		return new Node\Number($left[1] * $right[1], $left[2]);
+	}
+
+	/**
+	 * Subtract numbers
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return \ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function opSubNumberNumber($left, $right)
+	{
+		return new Node\Number($left[1] - $right[1], $left[2]);
+	}
+
+	/**
+	 * Divide numbers
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array|\ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function opDivNumberNumber($left, $right)
+	{
+		if ($right[1] == 0) {
+			return ($left[1] == 0) ? static::$NaN : static::$Infinity;
+		}
+
+		return new Node\Number($left[1] / $right[1], $left[2]);
+	}
+
+	/**
+	 * Mod numbers
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return \ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function opModNumberNumber($left, $right)
+	{
+		if ($right[1] == 0) {
+			return static::$NaN;
+		}
+
+		return new Node\Number($left[1] % $right[1], $left[2]);
+	}
+
+	/**
+	 * Add strings
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array|null
+	 */
+	protected function opAdd($left, $right)
+	{
+		if ($strLeft = $this->coerceString($left)) {
+			if ($right[0] === Type::T_STRING) {
+				$right[1] = '';
+			}
+
+			$strLeft[2][] = $right;
+
+			return $strLeft;
+		}
+
+		if ($strRight = $this->coerceString($right)) {
+			if ($left[0] === Type::T_STRING) {
+				$left[1] = '';
+			}
+
+			array_unshift($strRight[2], $left);
+
+			return $strRight;
+		}
+
+		return null;
+	}
+
+	/**
+	 * Boolean and
+	 *
+	 * @param array   $left
+	 * @param array   $right
+	 * @param boolean $shouldEval
+	 *
+	 * @return array|null
+	 */
+	protected function opAnd($left, $right, $shouldEval)
+	{
+		$truthy = ($left === static::$null || $right === static::$null) ||
+				  ($left === static::$false || $left === static::$true) &&
+				  ($right === static::$false || $right === static::$true);
+
+		if (! $shouldEval) {
+			if (! $truthy) {
+				return null;
+			}
+		}
+
+		if ($left !== static::$false && $left !== static::$null) {
+			return $this->reduce($right, true);
+		}
+
+		return $left;
+	}
+
+	/**
+	 * Boolean or
+	 *
+	 * @param array   $left
+	 * @param array   $right
+	 * @param boolean $shouldEval
+	 *
+	 * @return array|null
+	 */
+	protected function opOr($left, $right, $shouldEval)
+	{
+		$truthy = ($left === static::$null || $right === static::$null) ||
+				  ($left === static::$false || $left === static::$true) &&
+				  ($right === static::$false || $right === static::$true);
+
+		if (! $shouldEval) {
+			if (! $truthy) {
+				return null;
+			}
+		}
+
+		if ($left !== static::$false && $left !== static::$null) {
+			return $left;
+		}
+
+		return $this->reduce($right, true);
+	}
+
+	/**
+	 * Compare colors
+	 *
+	 * @param string $op
+	 * @param array  $left
+	 * @param array  $right
+	 *
+	 * @return array
+	 */
+	protected function opColorColor($op, $left, $right)
+	{
+		$out = [Type::T_COLOR];
+
+		foreach ([1, 2, 3] as $i) {
+			$lval = isset($left[$i]) ? $left[$i] : 0;
+			$rval = isset($right[$i]) ? $right[$i] : 0;
+
+			switch ($op) {
+				case '+':
+					$out[] = $lval + $rval;
+					break;
+
+				case '-':
+					$out[] = $lval - $rval;
+					break;
+
+				case '*':
+					$out[] = $lval * $rval;
+					break;
+
+				case '%':
+					if ($rval == 0) {
+						throw $this->error("color: Can't take modulo by zero");
+					}
+
+					$out[] = $lval % $rval;
+					break;
+
+				case '/':
+					if ($rval == 0) {
+						throw $this->error("color: Can't divide by zero");
+					}
+
+					$out[] = (int) ($lval / $rval);
+					break;
+
+				case '==':
+					return $this->opEq($left, $right);
+
+				case '!=':
+					return $this->opNeq($left, $right);
+
+				default:
+					throw $this->error("color: unknown op $op");
+			}
+		}
+
+		if (isset($left[4])) {
+			$out[4] = $left[4];
+		} elseif (isset($right[4])) {
+			$out[4] = $right[4];
+		}
+
+		return $this->fixColor($out);
+	}
+
+	/**
+	 * Compare color and number
+	 *
+	 * @param string $op
+	 * @param array  $left
+	 * @param array  $right
+	 *
+	 * @return array
+	 */
+	protected function opColorNumber($op, $left, $right)
+	{
+		$value = $right[1];
+
+		return $this->opColorColor(
+			$op,
+			$left,
+			[Type::T_COLOR, $value, $value, $value]
+		);
+	}
+
+	/**
+	 * Compare number and color
+	 *
+	 * @param string $op
+	 * @param array  $left
+	 * @param array  $right
+	 *
+	 * @return array
+	 */
+	protected function opNumberColor($op, $left, $right)
+	{
+		$value = $left[1];
+
+		return $this->opColorColor(
+			$op,
+			[Type::T_COLOR, $value, $value, $value],
+			$right
+		);
+	}
+
+	/**
+	 * Compare number1 == number2
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array
+	 */
+	protected function opEq($left, $right)
+	{
+		if (($lStr = $this->coerceString($left)) && ($rStr = $this->coerceString($right))) {
+			$lStr[1] = '';
+			$rStr[1] = '';
+
+			$left = $this->compileValue($lStr);
+			$right = $this->compileValue($rStr);
+		}
+
+		return $this->toBool($left === $right);
+	}
+
+	/**
+	 * Compare number1 != number2
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array
+	 */
+	protected function opNeq($left, $right)
+	{
+		if (($lStr = $this->coerceString($left)) && ($rStr = $this->coerceString($right))) {
+			$lStr[1] = '';
+			$rStr[1] = '';
+
+			$left = $this->compileValue($lStr);
+			$right = $this->compileValue($rStr);
+		}
+
+		return $this->toBool($left !== $right);
+	}
+
+	/**
+	 * Compare number1 >= number2
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array
+	 */
+	protected function opGteNumberNumber($left, $right)
+	{
+		return $this->toBool($left[1] >= $right[1]);
+	}
+
+	/**
+	 * Compare number1 > number2
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array
+	 */
+	protected function opGtNumberNumber($left, $right)
+	{
+		return $this->toBool($left[1] > $right[1]);
+	}
+
+	/**
+	 * Compare number1 <= number2
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array
+	 */
+	protected function opLteNumberNumber($left, $right)
+	{
+		return $this->toBool($left[1] <= $right[1]);
+	}
+
+	/**
+	 * Compare number1 < number2
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return array
+	 */
+	protected function opLtNumberNumber($left, $right)
+	{
+		return $this->toBool($left[1] < $right[1]);
+	}
+
+	/**
+	 * Three-way comparison, aka spaceship operator
+	 *
+	 * @param array $left
+	 * @param array $right
+	 *
+	 * @return \ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function opCmpNumberNumber($left, $right)
+	{
+		$n = $left[1] - $right[1];
+
+		return new Node\Number($n ? $n / abs($n) : 0, '');
+	}
+
+	/**
+	 * Cast to boolean
+	 *
+	 * @api
+	 *
+	 * @param mixed $thing
+	 *
+	 * @return array
+	 */
+	public function toBool($thing)
+	{
+		return $thing ? static::$true : static::$false;
+	}
+
+	/**
+	 * Compiles a primitive value into a CSS property value.
+	 *
+	 * Values in scssphp are typed by being wrapped in arrays, their format is
+	 * typically:
+	 *
+	 *     array(type, contents [, additional_contents]*)
+	 *
+	 * The input is expected to be reduced. This function will not work on
+	 * things like expressions and variables.
+	 *
+	 * @api
+	 *
+	 * @param array $value
+	 *
+	 * @return string|array
+	 */
+	public function compileValue($value)
+	{
+		$value = $this->reduce($value);
+
+		switch ($value[0]) {
+			case Type::T_KEYWORD:
+				return $value[1];
+
+			case Type::T_COLOR:
+				// [1] - red component (either number for a %)
+				// [2] - green component
+				// [3] - blue component
+				// [4] - optional alpha component
+				list(, $r, $g, $b) = $value;
+
+				$r = $this->compileRGBAValue($r);
+				$g = $this->compileRGBAValue($g);
+				$b = $this->compileRGBAValue($b);
+
+				if (\count($value) === 5) {
+					$alpha = $this->compileRGBAValue($value[4], true);
+
+					if (! is_numeric($alpha) || $alpha < 1) {
+						$colorName = Colors::RGBaToColorName($r, $g, $b, $alpha);
+
+						if (! \is_null($colorName)) {
+							return $colorName;
+						}
+
+						if (is_numeric($alpha)) {
+							$a = new Node\Number($alpha, '');
+						} else {
+							$a = $alpha;
+						}
+
+						return 'rgba(' . $r . ', ' . $g . ', ' . $b . ', ' . $a . ')';
+					}
+				}
+
+				if (! is_numeric($r) || ! is_numeric($g) || ! is_numeric($b)) {
+					return 'rgb(' . $r . ', ' . $g . ', ' . $b . ')';
+				}
+
+				$colorName = Colors::RGBaToColorName($r, $g, $b);
+
+				if (! \is_null($colorName)) {
+					return $colorName;
+				}
+
+				$h = sprintf('#%02x%02x%02x', $r, $g, $b);
+
+				// Converting hex color to short notation (e.g. #003399 to #039)
+				if ($h[1] === $h[2] && $h[3] === $h[4] && $h[5] === $h[6]) {
+					$h = '#' . $h[1] . $h[3] . $h[5];
+				}
+
+				return $h;
+
+			case Type::T_NUMBER:
+				return $value->output($this);
+
+			case Type::T_STRING:
+				$content = $this->compileStringContent($value);
+
+				if ($value[1]) {
+					// force double quote as string quote for the output in certain cases
+					if (
+						$value[1] === "'" &&
+						strpos($content, '"') === false &&
+						strpbrk($content, '{}') !== false
+					) {
+						$value[1] = '"';
+					}
+					$content = str_replace(
+						array('\\a', "\n", "\f" , '\\'  , "\r" , $value[1]),
+						array("\r" , ' ' , '\\f', '\\\\', '\\a', '\\' . $value[1]),
+						$content
+					);
+				}
+
+				return $value[1] . $content . $value[1];
+
+			case Type::T_FUNCTION:
+				$args = ! empty($value[2]) ? $this->compileValue($value[2]) : '';
+
+				return "$value[1]($args)";
+
+			case Type::T_FUNCTION_REFERENCE:
+				$name = ! empty($value[2]) ? $value[2] : '';
+
+				return "get-function(\"$name\")";
+
+			case Type::T_LIST:
+				$value = $this->extractInterpolation($value);
+
+				if ($value[0] !== Type::T_LIST) {
+					return $this->compileValue($value);
+				}
 
-                list(, $delim, $items) = $value;
-                $pre = $post = '';
+				list(, $delim, $items) = $value;
+				$pre = $post = '';
 
-                if (! empty($value['enclosing'])) {
-                    switch ($value['enclosing']) {
-                        case 'parent':
-                            //$pre = '(';
-                            //$post = ')';
-                            break;
-                        case 'forced_parent':
-                            $pre = '(';
-                            $post = ')';
-                            break;
-                        case 'bracket':
-                        case 'forced_bracket':
-                            $pre = '[';
-                            $post = ']';
-                            break;
-                    }
-                }
+				if (! empty($value['enclosing'])) {
+					switch ($value['enclosing']) {
+						case 'parent':
+							//$pre = '(';
+							//$post = ')';
+							break;
+						case 'forced_parent':
+							$pre = '(';
+							$post = ')';
+							break;
+						case 'bracket':
+						case 'forced_bracket':
+							$pre = '[';
+							$post = ']';
+							break;
+					}
+				}
 
-                $prefix_value = '';
+				$prefix_value = '';
 
-                if ($delim !== ' ') {
-                    $prefix_value = ' ';
-                }
+				if ($delim !== ' ') {
+					$prefix_value = ' ';
+				}
 
-                $filtered = [];
+				$filtered = [];
 
-                foreach ($items as $item) {
-                    if ($item[0] === Type::T_NULL) {
-                        continue;
-                    }
+				foreach ($items as $item) {
+					if ($item[0] === Type::T_NULL) {
+						continue;
+					}
 
-                    $compiled = $this->compileValue($item);
+					$compiled = $this->compileValue($item);
 
-                    if ($prefix_value && \strlen($compiled)) {
-                        $compiled = $prefix_value . $compiled;
-                    }
+					if ($prefix_value && \strlen($compiled)) {
+						$compiled = $prefix_value . $compiled;
+					}
 
-                    $filtered[] = $compiled;
-                }
+					$filtered[] = $compiled;
+				}
 
-                return $pre . substr(implode("$delim", $filtered), \strlen($prefix_value)) . $post;
+				return $pre . substr(implode("$delim", $filtered), \strlen($prefix_value)) . $post;
 
-            case Type::T_MAP:
-                $keys     = $value[1];
-                $values   = $value[2];
-                $filtered = [];
+			case Type::T_MAP:
+				$keys     = $value[1];
+				$values   = $value[2];
+				$filtered = [];
 
-                for ($i = 0, $s = \count($keys); $i < $s; $i++) {
-                    $filtered[$this->compileValue($keys[$i])] = $this->compileValue($values[$i]);
-                }
+				for ($i = 0, $s = \count($keys); $i < $s; $i++) {
+					$filtered[$this->compileValue($keys[$i])] = $this->compileValue($values[$i]);
+				}
 
-                array_walk($filtered, function (&$value, $key) {
-                    $value = $key . ': ' . $value;
-                });
+				array_walk($filtered, function (&$value, $key) {
+					$value = $key . ': ' . $value;
+				});
 
-                return '(' . implode(', ', $filtered) . ')';
+				return '(' . implode(', ', $filtered) . ')';
 
-            case Type::T_INTERPOLATED:
-                // node created by extractInterpolation
-                list(, $interpolate, $left, $right) = $value;
-                list(,, $whiteLeft, $whiteRight) = $interpolate;
+			case Type::T_INTERPOLATED:
+				// node created by extractInterpolation
+				list(, $interpolate, $left, $right) = $value;
+				list(,, $whiteLeft, $whiteRight) = $interpolate;
 
-                $delim = $left[1];
-
-                if ($delim && $delim !== ' ' && ! $whiteLeft) {
-                    $delim .= ' ';
-                }
-
-                $left = \count($left[2]) > 0
-                    ?  $this->compileValue($left) . $delim . $whiteLeft
-                    : '';
-
-                $delim = $right[1];
+				$delim = $left[1];
+
+				if ($delim && $delim !== ' ' && ! $whiteLeft) {
+					$delim .= ' ';
+				}
+
+				$left = \count($left[2]) > 0
+					?  $this->compileValue($left) . $delim . $whiteLeft
+					: '';
+
+				$delim = $right[1];
 
-                if ($delim && $delim !== ' ') {
-                    $delim .= ' ';
-                }
+				if ($delim && $delim !== ' ') {
+					$delim .= ' ';
+				}
 
-                $right = \count($right[2]) > 0 ?
-                    $whiteRight . $delim . $this->compileValue($right) : '';
-
-                return $left . $this->compileValue($interpolate) . $right;
-
-            case Type::T_INTERPOLATE:
-                // strip quotes if it's a string
-                $reduced = $this->reduce($value[1]);
-
-                switch ($reduced[0]) {
-                    case Type::T_LIST:
-                        $reduced = $this->extractInterpolation($reduced);
-
-                        if ($reduced[0] !== Type::T_LIST) {
-                            break;
-                        }
-
-                        list(, $delim, $items) = $reduced;
-
-                        if ($delim !== ' ') {
-                            $delim .= ' ';
-                        }
-
-                        $filtered = [];
-
-                        foreach ($items as $item) {
-                            if ($item[0] === Type::T_NULL) {
-                                continue;
-                            }
-
-                            $temp = $this->compileValue([Type::T_KEYWORD, $item]);
-
-                            if ($temp[0] === Type::T_STRING) {
-                                $filtered[] = $this->compileStringContent($temp);
-                            } elseif ($temp[0] === Type::T_KEYWORD) {
-                                $filtered[] = $temp[1];
-                            } else {
-                                $filtered[] = $this->compileValue($temp);
-                            }
-                        }
-
-                        $reduced = [Type::T_KEYWORD, implode("$delim", $filtered)];
-                        break;
-
-                    case Type::T_STRING:
-                        $reduced = [Type::T_KEYWORD, $this->compileStringContent($reduced)];
-                        break;
-
-                    case Type::T_NULL:
-                        $reduced = [Type::T_KEYWORD, ''];
-                }
-
-                return $this->compileValue($reduced);
-
-            case Type::T_NULL:
-                return 'null';
-
-            case Type::T_COMMENT:
-                return $this->compileCommentValue($value);
-
-            default:
-                throw $this->error('unknown value type: ' . json_encode($value));
-        }
-    }
-
-    /**
-     * @param array $value
-     *
-     * @return array|string
-     */
-    protected function compileDebugValue($value)
-    {
-        $value = $this->reduce($value, true);
-
-        switch ($value[0]) {
-            case Type::T_STRING:
-                return $this->compileStringContent($value);
-
-            default:
-                return $this->compileValue($value);
-        }
-    }
-
-    /**
-     * Flatten list
-     *
-     * @param array $list
-     *
-     * @return string
-     */
-    protected function flattenList($list)
-    {
-        return $this->compileValue($list);
-    }
-
-    /**
-     * Compile string content
-     *
-     * @param array $string
-     *
-     * @return string
-     */
-    protected function compileStringContent($string)
-    {
-        $parts = [];
-
-        foreach ($string[2] as $part) {
-            if (\is_array($part) || $part instanceof \ArrayAccess) {
-                $parts[] = $this->compileValue($part);
-            } else {
-                $parts[] = $part;
-            }
-        }
-
-        return implode($parts);
-    }
-
-    /**
-     * Extract interpolation; it doesn't need to be recursive, compileValue will handle that
-     *
-     * @param array $list
-     *
-     * @return array
-     */
-    protected function extractInterpolation($list)
-    {
-        $items = $list[2];
-
-        foreach ($items as $i => $item) {
-            if ($item[0] === Type::T_INTERPOLATE) {
-                $before = [Type::T_LIST, $list[1], \array_slice($items, 0, $i)];
-                $after  = [Type::T_LIST, $list[1], \array_slice($items, $i + 1)];
-
-                return [Type::T_INTERPOLATED, $item, $before, $after];
-            }
-        }
-
-        return $list;
-    }
-
-    /**
-     * Find the final set of selectors
-     *
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     * @param \ScssPhp\ScssPhp\Block                $selfParent
-     *
-     * @return array
-     */
-    protected function multiplySelectors(Environment $env, $selfParent = null)
-    {
-        $envs            = $this->compactEnv($env);
-        $selectors       = [];
-        $parentSelectors = [[]];
-
-        $selfParentSelectors = null;
-
-        if (! \is_null($selfParent) && $selfParent->selectors) {
-            $selfParentSelectors = $this->evalSelectors($selfParent->selectors);
-        }
-
-        while ($env = array_pop($envs)) {
-            if (empty($env->selectors)) {
-                continue;
-            }
-
-            $selectors = $env->selectors;
-
-            do {
-                $stillHasSelf  = false;
-                $prevSelectors = $selectors;
-                $selectors     = [];
-
-                foreach ($parentSelectors as $parent) {
-                    foreach ($prevSelectors as $selector) {
-                        if ($selfParentSelectors) {
-                            foreach ($selfParentSelectors as $selfParent) {
-                                // if no '&' in the selector, each call will give same result, only add once
-                                $s = $this->joinSelectors($parent, $selector, $stillHasSelf, $selfParent);
-                                $selectors[serialize($s)] = $s;
-                            }
-                        } else {
-                            $s = $this->joinSelectors($parent, $selector, $stillHasSelf);
-                            $selectors[serialize($s)] = $s;
-                        }
-                    }
-                }
-            } while ($stillHasSelf);
-
-            $parentSelectors = $selectors;
-        }
-
-        $selectors = array_values($selectors);
-
-        // case we are just starting a at-root : nothing to multiply but parentSelectors
-        if (! $selectors && $selfParentSelectors) {
-            $selectors = $selfParentSelectors;
-        }
-
-        return $selectors;
-    }
-
-    /**
-     * Join selectors; looks for & to replace, or append parent before child
-     *
-     * @param array   $parent
-     * @param array   $child
-     * @param boolean $stillHasSelf
-     * @param array   $selfParentSelectors
-
-     * @return array
-     */
-    protected function joinSelectors($parent, $child, &$stillHasSelf, $selfParentSelectors = null)
-    {
-        $setSelf = false;
-        $out = [];
-
-        foreach ($child as $part) {
-            $newPart = [];
-
-            foreach ($part as $p) {
-                // only replace & once and should be recalled to be able to make combinations
-                if ($p === static::$selfSelector && $setSelf) {
-                    $stillHasSelf = true;
-                }
-
-                if ($p === static::$selfSelector && ! $setSelf) {
-                    $setSelf = true;
-
-                    if (\is_null($selfParentSelectors)) {
-                        $selfParentSelectors = $parent;
-                    }
-
-                    foreach ($selfParentSelectors as $i => $parentPart) {
-                        if ($i > 0) {
-                            $out[] = $newPart;
-                            $newPart = [];
-                        }
-
-                        foreach ($parentPart as $pp) {
-                            if (\is_array($pp)) {
-                                $flatten = [];
-
-                                array_walk_recursive($pp, function ($a) use (&$flatten) {
-                                    $flatten[] = $a;
-                                });
-
-                                $pp = implode($flatten);
-                            }
-
-                            $newPart[] = $pp;
-                        }
-                    }
-                } else {
-                    $newPart[] = $p;
-                }
-            }
-
-            $out[] = $newPart;
-        }
-
-        return $setSelf ? $out : array_merge($parent, $child);
-    }
-
-    /**
-     * Multiply media
-     *
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     * @param array                                 $childQueries
-     *
-     * @return array
-     */
-    protected function multiplyMedia(Environment $env = null, $childQueries = null)
-    {
-        if (
-            ! isset($env) ||
-            ! empty($env->block->type) && $env->block->type !== Type::T_MEDIA
-        ) {
-            return $childQueries;
-        }
-
-        // plain old block, skip
-        if (empty($env->block->type)) {
-            return $this->multiplyMedia($env->parent, $childQueries);
-        }
-
-        $parentQueries = isset($env->block->queryList)
-            ? $env->block->queryList
-            : [[[Type::T_MEDIA_VALUE, $env->block->value]]];
-
-        $store = [$this->env, $this->storeEnv];
-
-        $this->env      = $env;
-        $this->storeEnv = null;
-        $parentQueries  = $this->evaluateMediaQuery($parentQueries);
-
-        list($this->env, $this->storeEnv) = $store;
-
-        if (\is_null($childQueries)) {
-            $childQueries = $parentQueries;
-        } else {
-            $originalQueries = $childQueries;
-            $childQueries = [];
-
-            foreach ($parentQueries as $parentQuery) {
-                foreach ($originalQueries as $childQuery) {
-                    $childQueries[] = array_merge(
-                        $parentQuery,
-                        [[Type::T_MEDIA_TYPE, [Type::T_KEYWORD, 'all']]],
-                        $childQuery
-                    );
-                }
-            }
-        }
-
-        return $this->multiplyMedia($env->parent, $childQueries);
-    }
-
-    /**
-     * Convert env linked list to stack
-     *
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     *
-     * @return array
-     */
-    protected function compactEnv(Environment $env)
-    {
-        for ($envs = []; $env; $env = $env->parent) {
-            $envs[] = $env;
-        }
-
-        return $envs;
-    }
-
-    /**
-     * Convert env stack to singly linked list
-     *
-     * @param array $envs
-     *
-     * @return \ScssPhp\ScssPhp\Compiler\Environment
-     */
-    protected function extractEnv($envs)
-    {
-        for ($env = null; $e = array_pop($envs);) {
-            $e->parent = $env;
-            $env = $e;
-        }
-
-        return $env;
-    }
-
-    /**
-     * Push environment
-     *
-     * @param \ScssPhp\ScssPhp\Block $block
-     *
-     * @return \ScssPhp\ScssPhp\Compiler\Environment
-     */
-    protected function pushEnv(Block $block = null)
-    {
-        $env = new Environment();
-        $env->parent = $this->env;
-        $env->parentStore = $this->storeEnv;
-        $env->store  = [];
-        $env->block  = $block;
-        $env->depth  = isset($this->env->depth) ? $this->env->depth + 1 : 0;
-
-        $this->env = $env;
-        $this->storeEnv = null;
-
-        return $env;
-    }
-
-    /**
-     * Pop environment
-     */
-    protected function popEnv()
-    {
-        $this->storeEnv = $this->env->parentStore;
-        $this->env = $this->env->parent;
-    }
-
-    /**
-     * Propagate vars from a just poped Env (used in @each and @for)
-     *
-     * @param array      $store
-     * @param null|array $excludedVars
-     */
-    protected function backPropagateEnv($store, $excludedVars = null)
-    {
-        foreach ($store as $key => $value) {
-            if (empty($excludedVars) || ! \in_array($key, $excludedVars)) {
-                $this->set($key, $value, true);
-            }
-        }
-    }
-
-    /**
-     * Get store environment
-     *
-     * @return \ScssPhp\ScssPhp\Compiler\Environment
-     */
-    protected function getStoreEnv()
-    {
-        return isset($this->storeEnv) ? $this->storeEnv : $this->env;
-    }
-
-    /**
-     * Set variable
-     *
-     * @param string                                $name
-     * @param mixed                                 $value
-     * @param boolean                               $shadow
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     * @param mixed                                 $valueUnreduced
-     */
-    protected function set($name, $value, $shadow = false, Environment $env = null, $valueUnreduced = null)
-    {
-        $name = $this->normalizeName($name);
-
-        if (! isset($env)) {
-            $env = $this->getStoreEnv();
-        }
-
-        if ($shadow) {
-            $this->setRaw($name, $value, $env, $valueUnreduced);
-        } else {
-            $this->setExisting($name, $value, $env, $valueUnreduced);
-        }
-    }
-
-    /**
-     * Set existing variable
-     *
-     * @param string                                $name
-     * @param mixed                                 $value
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     * @param mixed                                 $valueUnreduced
-     */
-    protected function setExisting($name, $value, Environment $env, $valueUnreduced = null)
-    {
-        $storeEnv = $env;
-        $specialContentKey = static::$namespaces['special'] . 'content';
-
-        $hasNamespace = $name[0] === '^' || $name[0] === '@' || $name[0] === '%';
-
-        $maxDepth = 10000;
-
-        for (;;) {
-            if ($maxDepth-- <= 0) {
-                break;
-            }
-
-            if (\array_key_exists($name, $env->store)) {
-                break;
-            }
-
-            if (! $hasNamespace && isset($env->marker)) {
-                if (! empty($env->store[$specialContentKey])) {
-                    $env = $env->store[$specialContentKey]->scope;
-                    continue;
-                }
-
-                if (! empty($env->declarationScopeParent)) {
-                    $env = $env->declarationScopeParent;
-                    continue;
-                } else {
-                    $env = $storeEnv;
-                    break;
-                }
-            }
-
-            if (isset($env->parentStore)) {
-                $env = $env->parentStore;
-            } elseif (isset($env->parent)) {
-                $env = $env->parent;
-            } else {
-                $env = $storeEnv;
-                break;
-            }
-        }
-
-        $env->store[$name] = $value;
-
-        if ($valueUnreduced) {
-            $env->storeUnreduced[$name] = $valueUnreduced;
-        }
-    }
-
-    /**
-     * Set raw variable
-     *
-     * @param string                                $name
-     * @param mixed                                 $value
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     * @param mixed                                 $valueUnreduced
-     */
-    protected function setRaw($name, $value, Environment $env, $valueUnreduced = null)
-    {
-        $env->store[$name] = $value;
-
-        if ($valueUnreduced) {
-            $env->storeUnreduced[$name] = $valueUnreduced;
-        }
-    }
-
-    /**
-     * Get variable
-     *
-     * @api
-     *
-     * @param string                                $name
-     * @param boolean                               $shouldThrow
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     * @param boolean                               $unreduced
-     *
-     * @return mixed|null
-     */
-    public function get($name, $shouldThrow = true, Environment $env = null, $unreduced = false)
-    {
-        $normalizedName = $this->normalizeName($name);
-        $specialContentKey = static::$namespaces['special'] . 'content';
-
-        if (! isset($env)) {
-            $env = $this->getStoreEnv();
-        }
-
-        $hasNamespace = $normalizedName[0] === '^' || $normalizedName[0] === '@' || $normalizedName[0] === '%';
-
-        $maxDepth = 10000;
-
-        for (;;) {
-            if ($maxDepth-- <= 0) {
-                break;
-            }
-
-            if (\array_key_exists($normalizedName, $env->store)) {
-                if ($unreduced && isset($env->storeUnreduced[$normalizedName])) {
-                    return $env->storeUnreduced[$normalizedName];
-                }
-
-                return $env->store[$normalizedName];
-            }
-
-            if (! $hasNamespace && isset($env->marker)) {
-                if (! empty($env->store[$specialContentKey])) {
-                    $env = $env->store[$specialContentKey]->scope;
-                    continue;
-                }
-
-                if (! empty($env->declarationScopeParent)) {
-                    $env = $env->declarationScopeParent;
-                } else {
-                    $env = $this->rootEnv;
-                }
-                continue;
-            }
-
-            if (isset($env->parentStore)) {
-                $env = $env->parentStore;
-            } elseif (isset($env->parent)) {
-                $env = $env->parent;
-            } else {
-                break;
-            }
-        }
-
-        if ($shouldThrow) {
-            throw $this->error("Undefined variable \$$name" . ($maxDepth <= 0 ? ' (infinite recursion)' : ''));
-        }
-
-        // found nothing
-        return null;
-    }
-
-    /**
-     * Has variable?
-     *
-     * @param string                                $name
-     * @param \ScssPhp\ScssPhp\Compiler\Environment $env
-     *
-     * @return boolean
-     */
-    protected function has($name, Environment $env = null)
-    {
-        return ! \is_null($this->get($name, false, $env));
-    }
-
-    /**
-     * Inject variables
-     *
-     * @param array $args
-     */
-    protected function injectVariables(array $args)
-    {
-        if (empty($args)) {
-            return;
-        }
-
-        $parser = $this->parserFactory(__METHOD__);
-
-        foreach ($args as $name => $strValue) {
-            if ($name[0] === '$') {
-                $name = substr($name, 1);
-            }
-
-            if (! $parser->parseValue($strValue, $value)) {
-                $value = $this->coerceValue($strValue);
-            }
-
-            $this->set($name, $value);
-        }
-    }
-
-    /**
-     * Set variables
-     *
-     * @api
-     *
-     * @param array $variables
-     */
-    public function setVariables(array $variables)
-    {
-        $this->registeredVars = array_merge($this->registeredVars, $variables);
-    }
-
-    /**
-     * Unset variable
-     *
-     * @api
-     *
-     * @param string $name
-     */
-    public function unsetVariable($name)
-    {
-        unset($this->registeredVars[$name]);
-    }
-
-    /**
-     * Returns list of variables
-     *
-     * @api
-     *
-     * @return array
-     */
-    public function getVariables()
-    {
-        return $this->registeredVars;
-    }
-
-    /**
-     * Adds to list of parsed files
-     *
-     * @api
-     *
-     * @param string $path
-     */
-    public function addParsedFile($path)
-    {
-        if (isset($path) && is_file($path)) {
-            $this->parsedFiles[realpath($path)] = filemtime($path);
-        }
-    }
-
-    /**
-     * Returns list of parsed files
-     *
-     * @api
-     *
-     * @return array
-     */
-    public function getParsedFiles()
-    {
-        return $this->parsedFiles;
-    }
-
-    /**
-     * Add import path
-     *
-     * @api
-     *
-     * @param string|callable $path
-     */
-    public function addImportPath($path)
-    {
-        if (! \in_array($path, $this->importPaths)) {
-            $this->importPaths[] = $path;
-        }
-    }
-
-    /**
-     * Set import paths
-     *
-     * @api
-     *
-     * @param string|array $path
-     */
-    public function setImportPaths($path)
-    {
-        $this->importPaths = (array) $path;
-    }
-
-    /**
-     * Set number precision
-     *
-     * @api
-     *
-     * @param integer $numberPrecision
-     *
-     * @deprecated The number precision is not configurable anymore. The default is enough for all browsers.
-     */
-    public function setNumberPrecision($numberPrecision)
-    {
-        @trigger_error('The number precision is not configurable anymore. '
-            . 'The default is enough for all browsers.', E_USER_DEPRECATED);
-    }
-
-    /**
-     * Set formatter
-     *
-     * @api
-     *
-     * @param string $formatterName
-     */
-    public function setFormatter($formatterName)
-    {
-        $this->formatter = $formatterName;
-    }
-
-    /**
-     * Set line number style
-     *
-     * @api
-     *
-     * @param string $lineNumberStyle
-     */
-    public function setLineNumberStyle($lineNumberStyle)
-    {
-        $this->lineNumberStyle = $lineNumberStyle;
-    }
-
-    /**
-     * Enable/disable source maps
-     *
-     * @api
-     *
-     * @param integer $sourceMap
-     */
-    public function setSourceMap($sourceMap)
-    {
-        $this->sourceMap = $sourceMap;
-    }
-
-    /**
-     * Set source map options
-     *
-     * @api
-     *
-     * @param array $sourceMapOptions
-     */
-    public function setSourceMapOptions($sourceMapOptions)
-    {
-        $this->sourceMapOptions = $sourceMapOptions;
-    }
-
-    /**
-     * Register function
-     *
-     * @api
-     *
-     * @param string   $name
-     * @param callable $func
-     * @param array    $prototype
-     */
-    public function registerFunction($name, $func, $prototype = null)
-    {
-        $this->userFunctions[$this->normalizeName($name)] = [$func, $prototype];
-    }
-
-    /**
-     * Unregister function
-     *
-     * @api
-     *
-     * @param string $name
-     */
-    public function unregisterFunction($name)
-    {
-        unset($this->userFunctions[$this->normalizeName($name)]);
-    }
-
-    /**
-     * Add feature
-     *
-     * @api
-     *
-     * @param string $name
-     */
-    public function addFeature($name)
-    {
-        $this->registeredFeatures[$name] = true;
-    }
-
-    /**
-     * Import file
-     *
-     * @param string                                 $path
-     * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
-     */
-    protected function importFile($path, OutputBlock $out)
-    {
-        $this->pushCallStack('import ' . $path);
-        // see if tree is cached
-        $realPath = realpath($path);
-
-        if (isset($this->importCache[$realPath])) {
-            $this->handleImportLoop($realPath);
-
-            $tree = $this->importCache[$realPath];
-        } else {
-            $code   = file_get_contents($path);
-            $parser = $this->parserFactory($path);
-            $tree   = $parser->parse($code);
-
-            $this->importCache[$realPath] = $tree;
-        }
-
-        $pi = pathinfo($path);
-
-        array_unshift($this->importPaths, $pi['dirname']);
-        $this->compileChildrenNoReturn($tree->children, $out);
-        array_shift($this->importPaths);
-        $this->popCallStack();
-    }
-
-    /**
-     * Return the file path for an import url if it exists
-     *
-     * @api
-     *
-     * @param string $url
-     *
-     * @return string|null
-     */
-    public function findImport($url)
-    {
-        $urls = [];
-
-        $hasExtension = preg_match('/[.]s?css$/', $url);
-
-        // for "normal" scss imports (ignore vanilla css and external requests)
-        if (! preg_match('~\.css$|^https?://|^//~', $url)) {
-            $isPartial = (strpos(basename($url), '_') === 0);
-
-            // try both normal and the _partial filename
-            $urls = [$url . ($hasExtension ? '' : '.scss')];
-
-            if (! $isPartial) {
-                $urls[] = preg_replace('~[^/]+$~', '_\0', $url) . ($hasExtension ? '' : '.scss');
-            }
-
-            if (! $hasExtension) {
-                $urls[] = "$url/index.scss";
-                $urls[] = "$url/_index.scss";
-                // allow to find a plain css file, *if* no scss or partial scss is found
-                $urls[] .= $url . '.css';
-            }
-        }
-
-        foreach ($this->importPaths as $dir) {
-            if (\is_string($dir)) {
-                // check urls for normal import paths
-                foreach ($urls as $full) {
-                    $separator = (
-                        ! empty($dir) &&
-                        substr($dir, -1) !== '/' &&
-                        substr($full, 0, 1) !== '/'
-                    ) ? '/' : '';
-                    $full = $dir . $separator . $full;
-
-                    if (is_file($file = $full)) {
-                        return $file;
-                    }
-                }
-            } elseif (\is_callable($dir)) {
-                // check custom callback for import path
-                $file = \call_user_func($dir, $url);
-
-                if (! \is_null($file)) {
-                    return $file;
-                }
-            }
-        }
-
-        if ($urls) {
-            if (! $hasExtension || preg_match('/[.]scss$/', $url)) {
-                throw $this->error("`$url` file not found for @import");
-            }
-        }
-
-        return null;
-    }
-
-    /**
-     * Set encoding
-     *
-     * @api
-     *
-     * @param string $encoding
-     */
-    public function setEncoding($encoding)
-    {
-        $this->encoding = $encoding;
-    }
-
-    /**
-     * Ignore errors?
-     *
-     * @api
-     *
-     * @param boolean $ignoreErrors
-     *
-     * @return \ScssPhp\ScssPhp\Compiler
-     *
-     * @deprecated Ignoring Sass errors is not longer supported.
-     */
-    public function setIgnoreErrors($ignoreErrors)
-    {
-        @trigger_error('Ignoring Sass errors is not longer supported.', E_USER_DEPRECATED);
-
-        return $this;
-    }
-
-    /**
-     * Get source position
-     *
-     * @api
-     *
-     * @return array
-     */
-    public function getSourcePosition()
-    {
-        $sourceFile = isset($this->sourceNames[$this->sourceIndex]) ? $this->sourceNames[$this->sourceIndex] : '';
-
-        return [$sourceFile, $this->sourceLine, $this->sourceColumn];
-    }
-
-    /**
-     * Throw error (exception)
-     *
-     * @api
-     *
-     * @param string $msg Message with optional sprintf()-style vararg parameters
-     *
-     * @throws \ScssPhp\ScssPhp\Exception\CompilerException
-     *
-     * @deprecated use "error" and throw the exception in the caller instead.
-     */
-    public function throwError($msg)
-    {
-        @trigger_error(
-            'The method "throwError" is deprecated. Use "error" and throw the exception in the caller instead',
-            E_USER_DEPRECATED
-        );
-
-        throw $this->error(...func_get_args());
-    }
-
-    /**
-     * Build an error (exception)
-     *
-     * @api
-     *
-     * @param string $msg Message with optional sprintf()-style vararg parameters
-     *
-     * @return CompilerException
-     */
-    public function error($msg, ...$args)
-    {
-        if ($args) {
-            $msg = sprintf($msg, ...$args);
-        }
-
-        if (! $this->ignoreCallStackMessage) {
-            $line   = $this->sourceLine;
-            $column = $this->sourceColumn;
-
-            $loc = isset($this->sourceNames[$this->sourceIndex])
-                ? $this->sourceNames[$this->sourceIndex] . " on line $line, at column $column"
-                : "line: $line, column: $column";
-
-            $msg = "$msg: $loc";
-
-            $callStackMsg = $this->callStackMessage();
-
-            if ($callStackMsg) {
-                $msg .= "\nCall Stack:\n" . $callStackMsg;
-            }
-        }
-
-        return new CompilerException($msg);
-    }
-
-    /**
-     * @param string $functionName
-     * @param array $ExpectedArgs
-     * @param int $nbActual
-     * @return CompilerException
-     */
-    public function errorArgsNumber($functionName, $ExpectedArgs, $nbActual)
-    {
-        $nbExpected = \count($ExpectedArgs);
-
-        if ($nbActual > $nbExpected) {
-            return $this->error(
-                'Error: Only %d arguments allowed in %s(), but %d were passed.',
-                $nbExpected,
-                $functionName,
-                $nbActual
-            );
-        } else {
-            $missing = [];
-
-            while (count($ExpectedArgs) && count($ExpectedArgs) > $nbActual) {
-                array_unshift($missing, array_pop($ExpectedArgs));
-            }
-
-            return $this->error(
-                'Error: %s() argument%s %s missing.',
-                $functionName,
-                count($missing) > 1 ? 's' : '',
-                implode(', ', $missing)
-            );
-        }
-    }
-
-    /**
-     * Beautify call stack for output
-     *
-     * @param boolean $all
-     * @param null    $limit
-     *
-     * @return string
-     */
-    protected function callStackMessage($all = false, $limit = null)
-    {
-        $callStackMsg = [];
-        $ncall = 0;
-
-        if ($this->callStack) {
-            foreach (array_reverse($this->callStack) as $call) {
-                if ($all || (isset($call['n']) && $call['n'])) {
-                    $msg = '#' . $ncall++ . ' ' . $call['n'] . ' ';
-                    $msg .= (isset($this->sourceNames[$call[Parser::SOURCE_INDEX]])
-                          ? $this->sourceNames[$call[Parser::SOURCE_INDEX]]
-                          : '(unknown file)');
-                    $msg .= ' on line ' . $call[Parser::SOURCE_LINE];
-
-                    $callStackMsg[] = $msg;
-
-                    if (! \is_null($limit) && $ncall > $limit) {
-                        break;
-                    }
-                }
-            }
-        }
-
-        return implode("\n", $callStackMsg);
-    }
-
-    /**
-     * Handle import loop
-     *
-     * @param string $name
-     *
-     * @throws \Exception
-     */
-    protected function handleImportLoop($name)
-    {
-        for ($env = $this->env; $env; $env = $env->parent) {
-            if (! $env->block) {
-                continue;
-            }
-
-            $file = $this->sourceNames[$env->block->sourceIndex];
-
-            if (realpath($file) === $name) {
-                throw $this->error('An @import loop has been found: %s imports %s', $file, basename($file));
-            }
-        }
-    }
-
-    /**
-     * Call SCSS @function
-     *
-     * @param Object $func
-     * @param array  $argValues
-     *
-     * @return array $returnValue
-     */
-    protected function callScssFunction($func, $argValues)
-    {
-        if (! $func) {
-            return static::$defaultValue;
-        }
-        $name = $func->name;
-
-        $this->pushEnv();
-
-        // set the args
-        if (isset($func->args)) {
-            $this->applyArguments($func->args, $argValues);
-        }
-
-        // throw away lines and children
-        $tmp = new OutputBlock();
-        $tmp->lines    = [];
-        $tmp->children = [];
-
-        $this->env->marker = 'function';
-
-        if (! empty($func->parentEnv)) {
-            $this->env->declarationScopeParent = $func->parentEnv;
-        } else {
-            throw $this->error("@function $name() without parentEnv");
-        }
-
-        $ret = $this->compileChildren($func->children, $tmp, $this->env->marker . ' ' . $name);
-
-        $this->popEnv();
-
-        return ! isset($ret) ? static::$defaultValue : $ret;
-    }
-
-    /**
-     * Call built-in and registered (PHP) functions
-     *
-     * @param string $name
-     * @param string|array $function
-     * @param array  $prototype
-     * @param array  $args
-     *
-     * @return array
-     */
-    protected function callNativeFunction($name, $function, $prototype, $args)
-    {
-        $libName = (is_array($function) ? end($function) : null);
-        $sorted_kwargs = $this->sortNativeFunctionArgs($libName, $prototype, $args);
-
-        if (\is_null($sorted_kwargs)) {
-            return null;
-        }
-        @list($sorted, $kwargs) = $sorted_kwargs;
-
-        if ($name !== 'if' && $name !== 'call') {
-            $inExp = true;
-
-            if ($name === 'join') {
-                $inExp = false;
-            }
-
-            foreach ($sorted as &$val) {
-                $val = $this->reduce($val, $inExp);
-            }
-        }
-
-        $returnValue = \call_user_func($function, $sorted, $kwargs);
-
-        if (! isset($returnValue)) {
-            return null;
-        }
-
-        return $this->coerceValue($returnValue);
-    }
-
-    /**
-     * Get built-in function
-     *
-     * @param string $name Normalized name
-     *
-     * @return array
-     */
-    protected function getBuiltinFunction($name)
-    {
-        $libName = 'lib' . preg_replace_callback(
-            '/_(.)/',
-            function ($m) {
-                return ucfirst($m[1]);
-            },
-            ucfirst($name)
-        );
-
-        return [$this, $libName];
-    }
-
-    /**
-     * Sorts keyword arguments
-     *
-     * @param string $functionName
-     * @param array  $prototypes
-     * @param array  $args
-     *
-     * @return array|null
-     */
-    protected function sortNativeFunctionArgs($functionName, $prototypes, $args)
-    {
-        static $parser = null;
-
-        if (! isset($prototypes)) {
-            $keyArgs = [];
-            $posArgs = [];
-
-            if (\is_array($args) && \count($args) && \end($args) === static::$null) {
-                array_pop($args);
-            }
-
-            // separate positional and keyword arguments
-            foreach ($args as $arg) {
-                list($key, $value) = $arg;
-
-                if (empty($key) or empty($key[1])) {
-                    $posArgs[] = empty($arg[2]) ? $value : $arg;
-                } else {
-                    $keyArgs[$key[1]] = $value;
-                }
-            }
-
-            return [$posArgs, $keyArgs];
-        }
-
-        // specific cases ?
-        if (\in_array($functionName, ['libRgb', 'libRgba', 'libHsl', 'libHsla'])) {
-            // notation 100 127 255 / 0 is in fact a simple list of 4 values
-            foreach ($args as $k => $arg) {
-                if ($arg[1][0] === Type::T_LIST && \count($arg[1][2]) === 3) {
-                    $last = end($arg[1][2]);
-
-                    if ($last[0] === Type::T_EXPRESSION && $last[1] === '/') {
-                        array_pop($arg[1][2]);
-                        $arg[1][2][] = $last[2];
-                        $arg[1][2][] = $last[3];
-                        $args[$k] = $arg;
-                    }
-                }
-            }
-        }
-
-        $finalArgs = [];
-
-        if (! \is_array(reset($prototypes))) {
-            $prototypes = [$prototypes];
-        }
-
-        $keyArgs = [];
-
-        // trying each prototypes
-        $prototypeHasMatch = false;
-        $exceptionMessage = '';
-
-        foreach ($prototypes as $prototype) {
-            $argDef = [];
-
-            foreach ($prototype as $i => $p) {
-                $default = null;
-                $p       = explode(':', $p, 2);
-                $name    = array_shift($p);
-
-                if (\count($p)) {
-                    $p = trim(reset($p));
-
-                    if ($p === 'null') {
-                        // differentiate this null from the static::$null
-                        $default = [Type::T_KEYWORD, 'null'];
-                    } else {
-                        if (\is_null($parser)) {
-                            $parser = $this->parserFactory(__METHOD__);
-                        }
-
-                        $parser->parseValue($p, $default);
-                    }
-                }
-
-                $isVariable = false;
-
-                if (substr($name, -3) === '...') {
-                    $isVariable = true;
-                    $name = substr($name, 0, -3);
-                }
-
-                $argDef[] = [$name, $default, $isVariable];
-            }
-
-            $ignoreCallStackMessage = $this->ignoreCallStackMessage;
-            $this->ignoreCallStackMessage = true;
-
-            try {
-                if (\count($args) > \count($argDef)) {
-                    $lastDef = end($argDef);
-
-                    // check that last arg is not a ...
-                    if (empty($lastDef[2])) {
-                        throw $this->errorArgsNumber($functionName, $argDef, \count($args));
-                    }
-                }
-                $vars = $this->applyArguments($argDef, $args, false, false);
-
-                // ensure all args are populated
-                foreach ($prototype as $i => $p) {
-                    $name = explode(':', $p)[0];
-
-                    if (! isset($finalArgs[$i])) {
-                        $finalArgs[$i] = null;
-                    }
-                }
-
-                // apply positional args
-                foreach (array_values($vars) as $i => $val) {
-                    $finalArgs[$i] = $val;
-                }
-
-                $keyArgs = array_merge($keyArgs, $vars);
-                $prototypeHasMatch = true;
-
-                // overwrite positional args with keyword args
-                foreach ($prototype as $i => $p) {
-                    $name = explode(':', $p)[0];
-
-                    if (isset($keyArgs[$name])) {
-                        $finalArgs[$i] = $keyArgs[$name];
-                    }
-
-                    // special null value as default: translate to real null here
-                    if ($finalArgs[$i] === [Type::T_KEYWORD, 'null']) {
-                        $finalArgs[$i] = null;
-                    }
-                }
-                // should we break if this prototype seems fulfilled?
-            } catch (CompilerException $e) {
-                $exceptionMessage = $e->getMessage();
-            }
-            $this->ignoreCallStackMessage = $ignoreCallStackMessage;
-        }
-
-        if ($exceptionMessage && ! $prototypeHasMatch) {
-            if (\in_array($functionName, ['libRgb', 'libRgba', 'libHsl', 'libHsla'])) {
-                // if var() or calc() is used as an argument, return as a css function
-                foreach ($args as $arg) {
-                    if ($arg[1][0] === Type::T_FUNCTION_CALL && in_array($arg[1][1], ['var'])) {
-                        return null;
-                    }
-                }
-            }
-
-            throw $this->error($exceptionMessage);
-        }
-
-        return [$finalArgs, $keyArgs];
-    }
-
-    /**
-     * Apply argument values per definition
-     *
-     * @param array   $argDef
-     * @param array   $argValues
-     * @param boolean $storeInEnv
-     * @param boolean $reduce
-     *   only used if $storeInEnv = false
-     *
-     * @return array
-     *
-     * @throws \Exception
-     */
-    protected function applyArguments($argDef, $argValues, $storeInEnv = true, $reduce = true)
-    {
-        $output = [];
-
-        if (\is_array($argValues) && \count($argValues) && end($argValues) === static::$null) {
-            array_pop($argValues);
-        }
-
-        if ($storeInEnv) {
-            $storeEnv = $this->getStoreEnv();
-
-            $env = new Environment();
-            $env->store = $storeEnv->store;
-        }
-
-        $hasVariable = false;
-        $args = [];
-
-        foreach ($argDef as $i => $arg) {
-            list($name, $default, $isVariable) = $argDef[$i];
-
-            $args[$name] = [$i, $name, $default, $isVariable];
-            $hasVariable |= $isVariable;
-        }
-
-        $splatSeparator      = null;
-        $keywordArgs         = [];
-        $deferredKeywordArgs = [];
-        $deferredNamedKeywordArgs = [];
-        $remaining           = [];
-        $hasKeywordArgument  = false;
-
-        // assign the keyword args
-        foreach ((array) $argValues as $arg) {
-            if (! empty($arg[0])) {
-                $hasKeywordArgument = true;
-
-                $name = $arg[0][1];
-
-                if (! isset($args[$name])) {
-                    foreach (array_keys($args) as $an) {
-                        if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
-                            $name = $an;
-                            break;
-                        }
-                    }
-                }
-
-                if (! isset($args[$name]) || $args[$name][3]) {
-                    if ($hasVariable) {
-                        $deferredNamedKeywordArgs[$name] = $arg[1];
-                    } else {
-                        throw $this->error("Mixin or function doesn't have an argument named $%s.", $arg[0][1]);
-                    }
-                } elseif ($args[$name][0] < \count($remaining)) {
-                    throw $this->error("The argument $%s was passed both by position and by name.", $arg[0][1]);
-                } else {
-                    $keywordArgs[$name] = $arg[1];
-                }
-            } elseif (! empty($arg[2])) {
-                // $arg[2] means a var followed by ... in the arg ($list... )
-                $val = $this->reduce($arg[1], true);
-
-                if ($val[0] === Type::T_LIST) {
-                    foreach ($val[2] as $name => $item) {
-                        if (! is_numeric($name)) {
-                            if (! isset($args[$name])) {
-                                foreach (array_keys($args) as $an) {
-                                    if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
-                                        $name = $an;
-                                        break;
-                                    }
-                                }
-                            }
-
-                            if ($hasVariable) {
-                                $deferredKeywordArgs[$name] = $item;
-                            } else {
-                                $keywordArgs[$name] = $item;
-                            }
-                        } else {
-                            if (\is_null($splatSeparator)) {
-                                $splatSeparator = $val[1];
-                            }
-
-                            $remaining[] = $item;
-                        }
-                    }
-                } elseif ($val[0] === Type::T_MAP) {
-                    foreach ($val[1] as $i => $name) {
-                        $name = $this->compileStringContent($this->coerceString($name));
-                        $item = $val[2][$i];
-
-                        if (! is_numeric($name)) {
-                            if (! isset($args[$name])) {
-                                foreach (array_keys($args) as $an) {
-                                    if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
-                                        $name = $an;
-                                        break;
-                                    }
-                                }
-                            }
-
-                            if ($hasVariable) {
-                                $deferredKeywordArgs[$name] = $item;
-                            } else {
-                                $keywordArgs[$name] = $item;
-                            }
-                        } else {
-                            if (\is_null($splatSeparator)) {
-                                $splatSeparator = $val[1];
-                            }
-
-                            $remaining[] = $item;
-                        }
-                    }
-                } else {
-                    $remaining[] = $val;
-                }
-            } elseif ($hasKeywordArgument) {
-                throw $this->error('Positional arguments must come before keyword arguments.');
-            } else {
-                $remaining[] = $arg[1];
-            }
-        }
-
-        foreach ($args as $arg) {
-            list($i, $name, $default, $isVariable) = $arg;
-
-            if ($isVariable) {
-                // only if more than one arg : can not be passed as position and value
-                // see https://github.com/sass/libsass/issues/2927
-                if (count($args) > 1) {
-                    if (isset($remaining[$i]) && isset($deferredNamedKeywordArgs[$name])) {
-                        throw $this->error("The argument $%s was passed both by position and by name.", $name);
-                    }
-                }
-
-                $val = [Type::T_LIST, \is_null($splatSeparator) ? ',' : $splatSeparator , [], $isVariable];
-
-                for ($count = \count($remaining); $i < $count; $i++) {
-                    $val[2][] = $remaining[$i];
-                }
-
-                foreach ($deferredKeywordArgs as $itemName => $item) {
-                    $val[2][$itemName] = $item;
-                }
-
-                foreach ($deferredNamedKeywordArgs as $itemName => $item) {
-                    $val[2][$itemName] = $item;
-                }
-            } elseif (isset($remaining[$i])) {
-                $val = $remaining[$i];
-            } elseif (isset($keywordArgs[$name])) {
-                $val = $keywordArgs[$name];
-            } elseif (! empty($default)) {
-                continue;
-            } else {
-                throw $this->error("Missing argument $name");
-            }
-
-            if ($storeInEnv) {
-                $this->set($name, $this->reduce($val, true), true, $env);
-            } else {
-                $output[$name] = ($reduce ? $this->reduce($val, true) : $val);
-            }
-        }
-
-        if ($storeInEnv) {
-            $storeEnv->store = $env->store;
-        }
-
-        foreach ($args as $arg) {
-            list($i, $name, $default, $isVariable) = $arg;
-
-            if ($isVariable || isset($remaining[$i]) || isset($keywordArgs[$name]) || empty($default)) {
-                continue;
-            }
-
-            if ($storeInEnv) {
-                $this->set($name, $this->reduce($default, true), true);
-            } else {
-                $output[$name] = ($reduce ? $this->reduce($default, true) : $default);
-            }
-        }
-
-        return $output;
-    }
-
-    /**
-     * Coerce a php value into a scss one
-     *
-     * @param mixed $value
-     *
-     * @return array|\ScssPhp\ScssPhp\Node\Number
-     */
-    protected function coerceValue($value)
-    {
-        if (\is_array($value) || $value instanceof \ArrayAccess) {
-            return $value;
-        }
-
-        if (\is_bool($value)) {
-            return $this->toBool($value);
-        }
-
-        if (\is_null($value)) {
-            return static::$null;
-        }
-
-        if (is_numeric($value)) {
-            return new Node\Number($value, '');
-        }
-
-        if ($value === '') {
-            return static::$emptyString;
-        }
-
-        $value = [Type::T_KEYWORD, $value];
-        $color = $this->coerceColor($value);
-
-        if ($color) {
-            return $color;
-        }
-
-        return $value;
-    }
-
-    /**
-     * Coerce something to map
-     *
-     * @param array $item
-     *
-     * @return array
-     */
-    protected function coerceMap($item)
-    {
-        if ($item[0] === Type::T_MAP) {
-            return $item;
-        }
-
-        if (
-            $item[0] === static::$emptyList[0] &&
-            $item[1] === static::$emptyList[1] &&
-            $item[2] === static::$emptyList[2]
-        ) {
-            return static::$emptyMap;
-        }
-
-        return $item;
-    }
-
-    /**
-     * Coerce something to list
-     *
-     * @param array   $item
-     * @param string  $delim
-     * @param boolean $removeTrailingNull
-     *
-     * @return array
-     */
-    protected function coerceList($item, $delim = ',', $removeTrailingNull = false)
-    {
-        if (isset($item) && $item[0] === Type::T_LIST) {
-            // remove trailing null from the list
-            if ($removeTrailingNull && end($item[2]) === static::$null) {
-                array_pop($item[2]);
-            }
-
-            return $item;
-        }
-
-        if (isset($item) && $item[0] === Type::T_MAP) {
-            $keys = $item[1];
-            $values = $item[2];
-            $list = [];
-
-            for ($i = 0, $s = \count($keys); $i < $s; $i++) {
-                $key = $keys[$i];
-                $value = $values[$i];
-
-                switch ($key[0]) {
-                    case Type::T_LIST:
-                    case Type::T_MAP:
-                    case Type::T_STRING:
-                    case Type::T_NULL:
-                        break;
-
-                    default:
-                        $key = [Type::T_KEYWORD, $this->compileStringContent($this->coerceString($key))];
-                        break;
-                }
-
-                $list[] = [
-                    Type::T_LIST,
-                    '',
-                    [$key, $value]
-                ];
-            }
-
-            return [Type::T_LIST, ',', $list];
-        }
-
-        return [Type::T_LIST, $delim, ! isset($item) ? [] : [$item]];
-    }
-
-    /**
-     * Coerce color for expression
-     *
-     * @param array $value
-     *
-     * @return array|null
-     */
-    protected function coerceForExpression($value)
-    {
-        if ($color = $this->coerceColor($value)) {
-            return $color;
-        }
-
-        return $value;
-    }
-
-    /**
-     * Coerce value to color
-     *
-     * @param array $value
-     *
-     * @return array|null
-     */
-    protected function coerceColor($value, $inRGBFunction = false)
-    {
-        switch ($value[0]) {
-            case Type::T_COLOR:
-                for ($i = 1; $i <= 3; $i++) {
-                    if (! is_numeric($value[$i])) {
-                        $cv = $this->compileRGBAValue($value[$i]);
-
-                        if (! is_numeric($cv)) {
-                            return null;
-                        }
-
-                        $value[$i] = $cv;
-                    }
-
-                    if (isset($value[4])) {
-                        if (! is_numeric($value[4])) {
-                            $cv = $this->compileRGBAValue($value[4], true);
-
-                            if (! is_numeric($cv)) {
-                                return null;
-                            }
-
-                            $value[4] = $cv;
-                        }
-                    }
-                }
-
-                return $value;
-
-            case Type::T_LIST:
-                if ($inRGBFunction) {
-                    if (\count($value[2]) == 3 || \count($value[2]) == 4) {
-                        $color = $value[2];
-                        array_unshift($color, Type::T_COLOR);
-
-                        return $this->coerceColor($color);
-                    }
-                }
-
-                return null;
-
-            case Type::T_KEYWORD:
-                if (! \is_string($value[1])) {
-                    return null;
-                }
-
-                $name = strtolower($value[1]);
-
-                // hexa color?
-                if (preg_match('/^#([0-9a-f]+)$/i', $name, $m)) {
-                    $nofValues = \strlen($m[1]);
-
-                    if (\in_array($nofValues, [3, 4, 6, 8])) {
-                        $nbChannels = 3;
-                        $color      = [];
-                        $num        = hexdec($m[1]);
-
-                        switch ($nofValues) {
-                            case 4:
-                                $nbChannels = 4;
-                                // then continuing with the case 3:
-                            case 3:
-                                for ($i = 0; $i < $nbChannels; $i++) {
-                                    $t = $num & 0xf;
-                                    array_unshift($color, $t << 4 | $t);
-                                    $num >>= 4;
-                                }
-
-                                break;
-
-                            case 8:
-                                $nbChannels = 4;
-                                // then continuing with the case 6:
-                            case 6:
-                                for ($i = 0; $i < $nbChannels; $i++) {
-                                    array_unshift($color, $num & 0xff);
-                                    $num >>= 8;
-                                }
-
-                                break;
-                        }
-
-                        if ($nbChannels === 4) {
-                            if ($color[3] === 255) {
-                                $color[3] = 1; // fully opaque
-                            } else {
-                                $color[3] = round($color[3] / 255, Node\Number::PRECISION);
-                            }
-                        }
-
-                        array_unshift($color, Type::T_COLOR);
-
-                        return $color;
-                    }
-                }
-
-                if ($rgba = Colors::colorNameToRGBa($name)) {
-                    return isset($rgba[3])
-                        ? [Type::T_COLOR, $rgba[0], $rgba[1], $rgba[2], $rgba[3]]
-                        : [Type::T_COLOR, $rgba[0], $rgba[1], $rgba[2]];
-                }
-
-                return null;
-        }
-
-        return null;
-    }
-
-    /**
-     * @param integer|\ScssPhp\ScssPhp\Node\Number $value
-     * @param boolean                              $isAlpha
-     *
-     * @return integer|mixed
-     */
-    protected function compileRGBAValue($value, $isAlpha = false)
-    {
-        if ($isAlpha) {
-            return $this->compileColorPartValue($value, 0, 1, false);
-        }
-
-        return $this->compileColorPartValue($value, 0, 255, true);
-    }
-
-    /**
-     * @param mixed         $value
-     * @param integer|float $min
-     * @param integer|float $max
-     * @param boolean       $isInt
-     * @param boolean       $clamp
-     * @param boolean       $modulo
-     *
-     * @return integer|mixed
-     */
-    protected function compileColorPartValue($value, $min, $max, $isInt = true, $clamp = true, $modulo = false)
-    {
-        if (! is_numeric($value)) {
-            if (\is_array($value)) {
-                $reduced = $this->reduce($value);
-
-                if (\is_object($reduced) && $value->type === Type::T_NUMBER) {
-                    $value = $reduced;
-                }
-            }
-
-            if (\is_object($value) && $value->type === Type::T_NUMBER) {
-                $num = $value->dimension;
-
-                if (\count($value->units)) {
-                    $unit = array_keys($value->units);
-                    $unit = reset($unit);
-
-                    switch ($unit) {
-                        case '%':
-                            $num *= $max / 100;
-                            break;
-                        default:
-                            break;
-                    }
-                }
-
-                $value = $num;
-            } elseif (\is_array($value)) {
-                $value = $this->compileValue($value);
-            }
-        }
-
-        if (is_numeric($value)) {
-            if ($isInt) {
-                $value = round($value);
-            }
-
-            if ($clamp) {
-                $value = min($max, max($min, $value));
-            }
-
-            if ($modulo) {
-                $value = $value % $max;
-
-                // still negative?
-                while ($value < $min) {
-                    $value += $max;
-                }
-            }
-
-            return $value;
-        }
-
-        return $value;
-    }
-
-    /**
-     * Coerce value to string
-     *
-     * @param array $value
-     *
-     * @return array|null
-     */
-    protected function coerceString($value)
-    {
-        if ($value[0] === Type::T_STRING) {
-            return $value;
-        }
-
-        return [Type::T_STRING, '', [$this->compileValue($value)]];
-    }
-
-    /**
-     * Coerce value to a percentage
-     *
-     * @param array $value
-     *
-     * @return integer|float
-     */
-    protected function coercePercent($value)
-    {
-        if ($value[0] === Type::T_NUMBER) {
-            if (! empty($value[2]['%'])) {
-                return $value[1] / 100;
-            }
-
-            return $value[1];
-        }
-
-        return 0;
-    }
-
-    /**
-     * Assert value is a map
-     *
-     * @api
-     *
-     * @param array $value
-     *
-     * @return array
-     *
-     * @throws \Exception
-     */
-    public function assertMap($value)
-    {
-        $value = $this->coerceMap($value);
-
-        if ($value[0] !== Type::T_MAP) {
-            throw $this->error('expecting map, %s received', $value[0]);
-        }
-
-        return $value;
-    }
-
-    /**
-     * Assert value is a list
-     *
-     * @api
-     *
-     * @param array $value
-     *
-     * @return array
-     *
-     * @throws \Exception
-     */
-    public function assertList($value)
-    {
-        if ($value[0] !== Type::T_LIST) {
-            throw $this->error('expecting list, %s received', $value[0]);
-        }
-
-        return $value;
-    }
-
-    /**
-     * Assert value is a color
-     *
-     * @api
-     *
-     * @param array $value
-     *
-     * @return array
-     *
-     * @throws \Exception
-     */
-    public function assertColor($value)
-    {
-        if ($color = $this->coerceColor($value)) {
-            return $color;
-        }
-
-        throw $this->error('expecting color, %s received', $value[0]);
-    }
-
-    /**
-     * Assert value is a number
-     *
-     * @api
-     *
-     * @param array $value
-     *
-     * @return integer|float
-     *
-     * @throws \Exception
-     */
-    public function assertNumber($value)
-    {
-        if ($value[0] !== Type::T_NUMBER) {
-            throw $this->error('expecting number, %s received', $value[0]);
-        }
-
-        return $value[1];
-    }
-
-    /**
-     * Make sure a color's components don't go out of bounds
-     *
-     * @param array $c
-     *
-     * @return array
-     */
-    protected function fixColor($c)
-    {
-        foreach ([1, 2, 3] as $i) {
-            if ($c[$i] < 0) {
-                $c[$i] = 0;
-            }
-
-            if ($c[$i] > 255) {
-                $c[$i] = 255;
-            }
-        }
-
-        return $c;
-    }
-
-    /**
-     * Convert RGB to HSL
-     *
-     * @api
-     *
-     * @param integer $red
-     * @param integer $green
-     * @param integer $blue
-     *
-     * @return array
-     */
-    public function toHSL($red, $green, $blue)
-    {
-        $min = min($red, $green, $blue);
-        $max = max($red, $green, $blue);
-
-        $l = $min + $max;
-        $d = $max - $min;
-
-        if ((int) $d === 0) {
-            $h = $s = 0;
-        } else {
-            if ($l < 255) {
-                $s = $d / $l;
-            } else {
-                $s = $d / (510 - $l);
-            }
-
-            if ($red == $max) {
-                $h = 60 * ($green - $blue) / $d;
-            } elseif ($green == $max) {
-                $h = 60 * ($blue - $red) / $d + 120;
-            } elseif ($blue == $max) {
-                $h = 60 * ($red - $green) / $d + 240;
-            }
-        }
-
-        return [Type::T_HSL, fmod($h, 360), $s * 100, $l / 5.1];
-    }
-
-    /**
-     * Hue to RGB helper
-     *
-     * @param float $m1
-     * @param float $m2
-     * @param float $h
-     *
-     * @return float
-     */
-    protected function hueToRGB($m1, $m2, $h)
-    {
-        if ($h < 0) {
-            $h += 1;
-        } elseif ($h > 1) {
-            $h -= 1;
-        }
-
-        if ($h * 6 < 1) {
-            return $m1 + ($m2 - $m1) * $h * 6;
-        }
-
-        if ($h * 2 < 1) {
-            return $m2;
-        }
-
-        if ($h * 3 < 2) {
-            return $m1 + ($m2 - $m1) * (2 / 3 - $h) * 6;
-        }
-
-        return $m1;
-    }
-
-    /**
-     * Convert HSL to RGB
-     *
-     * @api
-     *
-     * @param integer $hue        H from 0 to 360
-     * @param integer $saturation S from 0 to 100
-     * @param integer $lightness  L from 0 to 100
-     *
-     * @return array
-     */
-    public function toRGB($hue, $saturation, $lightness)
-    {
-        if ($hue < 0) {
-            $hue += 360;
-        }
-
-        $h = $hue / 360;
-        $s = min(100, max(0, $saturation)) / 100;
-        $l = min(100, max(0, $lightness)) / 100;
-
-        $m2 = $l <= 0.5 ? $l * ($s + 1) : $l + $s - $l * $s;
-        $m1 = $l * 2 - $m2;
-
-        $r = $this->hueToRGB($m1, $m2, $h + 1 / 3) * 255;
-        $g = $this->hueToRGB($m1, $m2, $h) * 255;
-        $b = $this->hueToRGB($m1, $m2, $h - 1 / 3) * 255;
-
-        $out = [Type::T_COLOR, $r, $g, $b];
-
-        return $out;
-    }
-
-    // Built in functions
-
-    protected static $libCall = ['name', 'args...'];
-    protected function libCall($args, $kwargs)
-    {
-        $functionReference = $this->reduce(array_shift($args), true);
-
-        if (in_array($functionReference[0], [Type::T_STRING, Type::T_KEYWORD])) {
-            $name = $this->compileStringContent($this->coerceString($this->reduce($functionReference, true)));
-            $warning = "DEPRECATION WARNING: Passing a string to call() is deprecated and will be illegal\n"
-                . "in Sass 4.0. Use call(function-reference($name)) instead.";
-            fwrite($this->stderr, "$warning\n\n");
-            $functionReference = $this->libGetFunction([$functionReference]);
-        }
-
-        if ($functionReference === static::$null) {
-            return static::$null;
-        }
-
-        if (! in_array($functionReference[0], [Type::T_FUNCTION_REFERENCE, Type::T_FUNCTION])) {
-            throw $this->error('Function reference expected, got ' . $functionReference[0]);
-        }
-
-        $callArgs = [];
-
-        // $kwargs['args'] is [Type::T_LIST, ',', [..]]
-        foreach ($kwargs['args'][2] as $varname => $arg) {
-            if (is_numeric($varname)) {
-                $varname = null;
-            } else {
-                $varname = [ 'var', $varname];
-            }
-
-            $callArgs[] = [$varname, $arg, false];
-        }
-
-        return $this->reduce([Type::T_FUNCTION_CALL, $functionReference, $callArgs]);
-    }
-
-
-    protected static $libGetFunction = [
-        ['name'],
-        ['name', 'css']
-    ];
-    protected function libGetFunction($args)
-    {
-        $name = $this->compileStringContent($this->coerceString($this->reduce(array_shift($args), true)));
-        $isCss = false;
-
-        if (count($args)) {
-            $isCss = $this->reduce(array_shift($args), true);
-            $isCss = (($isCss === static::$true) ? true : false);
-        }
-
-        if ($isCss) {
-            return [Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]];
-        }
-
-        return $this->getFunctionReference($name, true);
-    }
-
-    protected static $libIf = ['condition', 'if-true', 'if-false:'];
-    protected function libIf($args)
-    {
-        list($cond, $t, $f) = $args;
-
-        if (! $this->isTruthy($this->reduce($cond, true))) {
-            return $this->reduce($f, true);
-        }
-
-        return $this->reduce($t, true);
-    }
-
-    protected static $libIndex = ['list', 'value'];
-    protected function libIndex($args)
-    {
-        list($list, $value) = $args;
-
-        if (
-            $list[0] === Type::T_MAP ||
-            $list[0] === Type::T_STRING ||
-            $list[0] === Type::T_KEYWORD ||
-            $list[0] === Type::T_INTERPOLATE
-        ) {
-            $list = $this->coerceList($list, ' ');
-        }
-
-        if ($list[0] !== Type::T_LIST) {
-            return static::$null;
-        }
-
-        $values = [];
-
-        foreach ($list[2] as $item) {
-            $values[] = $this->normalizeValue($item);
-        }
-
-        $key = array_search($this->normalizeValue($value), $values);
-
-        return false === $key ? static::$null : $key + 1;
-    }
-
-    protected static $libRgb = [
-        ['color'],
-        ['color', 'alpha'],
-        ['channels'],
-        ['red', 'green', 'blue'],
-        ['red', 'green', 'blue', 'alpha'] ];
-    protected function libRgb($args, $kwargs, $funcName = 'rgb')
-    {
-        switch (\count($args)) {
-            case 1:
-                if (! $color = $this->coerceColor($args[0], true)) {
-                    $color = [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
-                }
-                break;
-
-            case 3:
-                $color = [Type::T_COLOR, $args[0], $args[1], $args[2]];
-
-                if (! $color = $this->coerceColor($color)) {
-                    $color = [Type::T_STRING, '', [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ')']];
-                }
-
-                return $color;
-
-            case 2:
-                if ($color = $this->coerceColor($args[0], true)) {
-                    $alpha = $this->compileRGBAValue($args[1], true);
-
-                    if (is_numeric($alpha)) {
-                        $color[4] = $alpha;
-                    } else {
-                        $color = [Type::T_STRING, '',
-                            [$funcName . '(', $color[1], ', ', $color[2], ', ', $color[3], ', ', $alpha, ')']];
-                    }
-                } else {
-                    $color = [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
-                }
-                break;
-
-            case 4:
-            default:
-                $color = [Type::T_COLOR, $args[0], $args[1], $args[2], $args[3]];
-
-                if (! $color = $this->coerceColor($color)) {
-                    $color = [Type::T_STRING, '',
-                        [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ', ', $args[3], ')']];
-                }
-                break;
-        }
-
-        return $color;
-    }
-
-    protected static $libRgba = [
-        ['color'],
-        ['color', 'alpha'],
-        ['channels'],
-        ['red', 'green', 'blue'],
-        ['red', 'green', 'blue', 'alpha'] ];
-    protected function libRgba($args, $kwargs)
-    {
-        return $this->libRgb($args, $kwargs, 'rgba');
-    }
-
-    // helper function for adjust_color, change_color, and scale_color
-    protected function alterColor($args, $fn)
-    {
-        $color = $this->assertColor($args[0]);
-
-        foreach ([1 => 1, 2 => 2, 3 => 3, 7 => 4] as $iarg => $irgba) {
-            if (isset($args[$iarg])) {
-                $val = $this->assertNumber($args[$iarg]);
-
-                if (! isset($color[$irgba])) {
-                    $color[$irgba] = (($irgba < 4) ? 0 : 1);
-                }
-
-                $color[$irgba] = \call_user_func($fn, $color[$irgba], $val, $iarg);
-            }
-        }
-
-        if (! empty($args[4]) || ! empty($args[5]) || ! empty($args[6])) {
-            $hsl = $this->toHSL($color[1], $color[2], $color[3]);
-
-            foreach ([4 => 1, 5 => 2, 6 => 3] as $iarg => $ihsl) {
-                if (! empty($args[$iarg])) {
-                    $val = $this->assertNumber($args[$iarg]);
-                    $hsl[$ihsl] = \call_user_func($fn, $hsl[$ihsl], $val, $iarg);
-                }
-            }
-
-            $rgb = $this->toRGB($hsl[1], $hsl[2], $hsl[3]);
-
-            if (isset($color[4])) {
-                $rgb[4] = $color[4];
-            }
-
-            $color = $rgb;
-        }
-
-        return $color;
-    }
-
-    protected static $libAdjustColor = [
-        'color', 'red:null', 'green:null', 'blue:null',
-        'hue:null', 'saturation:null', 'lightness:null', 'alpha:null'
-    ];
-    protected function libAdjustColor($args)
-    {
-        return $this->alterColor($args, function ($base, $alter, $i) {
-            return $base + $alter;
-        });
-    }
-
-    protected static $libChangeColor = [
-        'color', 'red:null', 'green:null', 'blue:null',
-        'hue:null', 'saturation:null', 'lightness:null', 'alpha:null'
-    ];
-    protected function libChangeColor($args)
-    {
-        return $this->alterColor($args, function ($base, $alter, $i) {
-            return $alter;
-        });
-    }
-
-    protected static $libScaleColor = [
-        'color', 'red:null', 'green:null', 'blue:null',
-        'hue:null', 'saturation:null', 'lightness:null', 'alpha:null'
-    ];
-    protected function libScaleColor($args)
-    {
-        return $this->alterColor($args, function ($base, $scale, $i) {
-            // 1, 2, 3 - rgb
-            // 4, 5, 6 - hsl
-            // 7 - a
-            switch ($i) {
-                case 1:
-                case 2:
-                case 3:
-                    $max = 255;
-                    break;
-
-                case 4:
-                    $max = 360;
-                    break;
-
-                case 7:
-                    $max = 1;
-                    break;
-
-                default:
-                    $max = 100;
-            }
-
-            $scale = $scale / 100;
-
-            if ($scale < 0) {
-                return $base * $scale + $base;
-            }
-
-            return ($max - $base) * $scale + $base;
-        });
-    }
-
-    protected static $libIeHexStr = ['color'];
-    protected function libIeHexStr($args)
-    {
-        $color = $this->coerceColor($args[0]);
-
-        if (\is_null($color)) {
-            $this->throwError('Error: argument `$color` of `ie-hex-str($color)` must be a color');
-        }
-
-        $color[4] = isset($color[4]) ? round(255 * $color[4]) : 255;
-
-        return [Type::T_STRING, '', [sprintf('#%02X%02X%02X%02X', $color[4], $color[1], $color[2], $color[3])]];
-    }
-
-    protected static $libRed = ['color'];
-    protected function libRed($args)
-    {
-        $color = $this->coerceColor($args[0]);
-
-        if (\is_null($color)) {
-            $this->throwError('Error: argument `$color` of `red($color)` must be a color');
-        }
-
-        return $color[1];
-    }
-
-    protected static $libGreen = ['color'];
-    protected function libGreen($args)
-    {
-        $color = $this->coerceColor($args[0]);
-
-        if (\is_null($color)) {
-            $this->throwError('Error: argument `$color` of `green($color)` must be a color');
-        }
-
-        return $color[2];
-    }
-
-    protected static $libBlue = ['color'];
-    protected function libBlue($args)
-    {
-        $color = $this->coerceColor($args[0]);
-
-        if (\is_null($color)) {
-            $this->throwError('Error: argument `$color` of `blue($color)` must be a color');
-        }
-
-        return $color[3];
-    }
-
-    protected static $libAlpha = ['color'];
-    protected function libAlpha($args)
-    {
-        if ($color = $this->coerceColor($args[0])) {
-            return isset($color[4]) ? $color[4] : 1;
-        }
-
-        // this might be the IE function, so return value unchanged
-        return null;
-    }
-
-    protected static $libOpacity = ['color'];
-    protected function libOpacity($args)
-    {
-        $value = $args[0];
-
-        if ($value[0] === Type::T_NUMBER) {
-            return null;
-        }
-
-        return $this->libAlpha($args);
-    }
-
-    // mix two colors
-    protected static $libMix = [
-        ['color1', 'color2', 'weight:0.5'],
-        ['color-1', 'color-2', 'weight:0.5']
-        ];
-    protected function libMix($args)
-    {
-        list($first, $second, $weight) = $args;
-
-        $first = $this->assertColor($first);
-        $second = $this->assertColor($second);
-
-        if (! isset($weight)) {
-            $weight = 0.5;
-        } else {
-            $weight = $this->coercePercent($weight);
-        }
-
-        $firstAlpha = isset($first[4]) ? $first[4] : 1;
-        $secondAlpha = isset($second[4]) ? $second[4] : 1;
-
-        $w = $weight * 2 - 1;
-        $a = $firstAlpha - $secondAlpha;
-
-        $w1 = (($w * $a === -1 ? $w : ($w + $a) / (1 + $w * $a)) + 1) / 2.0;
-        $w2 = 1.0 - $w1;
-
-        $new = [Type::T_COLOR,
-            $w1 * $first[1] + $w2 * $second[1],
-            $w1 * $first[2] + $w2 * $second[2],
-            $w1 * $first[3] + $w2 * $second[3],
-        ];
-
-        if ($firstAlpha != 1.0 || $secondAlpha != 1.0) {
-            $new[] = $firstAlpha * $weight + $secondAlpha * (1 - $weight);
-        }
-
-        return $this->fixColor($new);
-    }
-
-    protected static $libHsl = [
-        ['channels'],
-        ['hue', 'saturation', 'lightness'],
-        ['hue', 'saturation', 'lightness', 'alpha'] ];
-    protected function libHsl($args, $kwargs, $funcName = 'hsl')
-    {
-        $args_to_check = $args;
-
-        if (\count($args) == 1) {
-            if ($args[0][0] !== Type::T_LIST || \count($args[0][2]) < 3 || \count($args[0][2]) > 4) {
-                return [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
-            }
-
-            $args = $args[0][2];
-            $args_to_check = $kwargs['channels'][2];
-        }
-
-        $hue = $this->compileColorPartValue($args[0], 0, 360, false, false, true);
-        $saturation = $this->compileColorPartValue($args[1], 0, 100, false);
-        $lightness = $this->compileColorPartValue($args[2], 0, 100, false);
-
-        foreach ($kwargs as $k => $arg) {
-            if (in_array($arg[0], [Type::T_FUNCTION_CALL]) && in_array($arg[1], ['min', 'max'])) {
-                return null;
-            }
-        }
-
-        foreach ($args_to_check as $k => $arg) {
-            if (in_array($arg[0], [Type::T_FUNCTION_CALL]) && in_array($arg[1], ['min', 'max'])) {
-                if (count($kwargs) > 1 || ($k >= 2 && count($args) === 4)) {
-                    return null;
-                }
-
-                $args[$k] = $this->stringifyFncallArgs($arg);
-                $hue = '';
-            }
-
-            if (
-                $k >= 2 && count($args) === 4 &&
-                in_array($arg[0], [Type::T_FUNCTION_CALL, Type::T_FUNCTION]) &&
-                in_array($arg[1], ['calc','env'])
-            ) {
-                return null;
-            }
-        }
-
-        $alpha = null;
-
-        if (\count($args) === 4) {
-            $alpha = $this->compileColorPartValue($args[3], 0, 100, false);
-
-            if (! is_numeric($hue) || ! is_numeric($saturation) || ! is_numeric($lightness) || ! is_numeric($alpha)) {
-                return [Type::T_STRING, '',
-                    [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ', ', $args[3], ')']];
-            }
-        } else {
-            if (! is_numeric($hue) || ! is_numeric($saturation) || ! is_numeric($lightness)) {
-                return [Type::T_STRING, '', [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ')']];
-            }
-        }
-
-        $color = $this->toRGB($hue, $saturation, $lightness);
-
-        if (! \is_null($alpha)) {
-            $color[4] = $alpha;
-        }
-
-        return $color;
-    }
-
-    protected static $libHsla = [
-            ['channels'],
-            ['hue', 'saturation', 'lightness'],
-            ['hue', 'saturation', 'lightness', 'alpha']];
-    protected function libHsla($args, $kwargs)
-    {
-        return $this->libHsl($args, $kwargs, 'hsla');
-    }
-
-    protected static $libHue = ['color'];
-    protected function libHue($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
-
-        return new Node\Number($hsl[1], 'deg');
-    }
-
-    protected static $libSaturation = ['color'];
-    protected function libSaturation($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
-
-        return new Node\Number($hsl[2], '%');
-    }
-
-    protected static $libLightness = ['color'];
-    protected function libLightness($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
-
-        return new Node\Number($hsl[3], '%');
-    }
-
-    protected function adjustHsl($color, $idx, $amount)
-    {
-        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
-        $hsl[$idx] += $amount;
-        $out = $this->toRGB($hsl[1], $hsl[2], $hsl[3]);
-
-        if (isset($color[4])) {
-            $out[4] = $color[4];
-        }
-
-        return $out;
-    }
-
-    protected static $libAdjustHue = ['color', 'degrees'];
-    protected function libAdjustHue($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $degrees = $this->assertNumber($args[1]);
-
-        return $this->adjustHsl($color, 1, $degrees);
-    }
-
-    protected static $libLighten = ['color', 'amount'];
-    protected function libLighten($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $amount = Util::checkRange('amount', new Range(0, 100), $args[1], '%');
-
-        return $this->adjustHsl($color, 3, $amount);
-    }
-
-    protected static $libDarken = ['color', 'amount'];
-    protected function libDarken($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $amount = Util::checkRange('amount', new Range(0, 100), $args[1], '%');
-
-        return $this->adjustHsl($color, 3, -$amount);
-    }
-
-    protected static $libSaturate = [['color', 'amount'], ['amount']];
-    protected function libSaturate($args)
-    {
-        $value = $args[0];
-
-        if ($value[0] === Type::T_NUMBER) {
-            return null;
-        }
-
-        if (count($args) === 1) {
-            $val = $this->compileValue($value);
-            throw $this->error("\$amount: $val is not a number");
-        }
-
-        $color = $this->assertColor($value);
-        $amount = 100 * $this->coercePercent($args[1]);
-
-        return $this->adjustHsl($color, 2, $amount);
-    }
-
-    protected static $libDesaturate = ['color', 'amount'];
-    protected function libDesaturate($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $amount = 100 * $this->coercePercent($args[1]);
-
-        return $this->adjustHsl($color, 2, -$amount);
-    }
-
-    protected static $libGrayscale = ['color'];
-    protected function libGrayscale($args)
-    {
-        $value = $args[0];
-
-        if ($value[0] === Type::T_NUMBER) {
-            return null;
-        }
-
-        return $this->adjustHsl($this->assertColor($value), 2, -100);
-    }
-
-    protected static $libComplement = ['color'];
-    protected function libComplement($args)
-    {
-        return $this->adjustHsl($this->assertColor($args[0]), 1, 180);
-    }
-
-    protected static $libInvert = ['color', 'weight:1'];
-    protected function libInvert($args)
-    {
-        list($value, $weight) = $args;
-
-        if (! isset($weight)) {
-            $weight = 1;
-        } else {
-            $weight = $this->coercePercent($weight);
-        }
-
-        if ($value[0] === Type::T_NUMBER) {
-            return null;
-        }
-
-        $color = $this->assertColor($value);
-        $inverted = $color;
-        $inverted[1] = 255 - $inverted[1];
-        $inverted[2] = 255 - $inverted[2];
-        $inverted[3] = 255 - $inverted[3];
-
-        if ($weight < 1) {
-            return $this->libMix([$inverted, $color, [Type::T_NUMBER, $weight]]);
-        }
-
-        return $inverted;
-    }
-
-    // increases opacity by amount
-    protected static $libOpacify = ['color', 'amount'];
-    protected function libOpacify($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $amount = $this->coercePercent($args[1]);
-
-        $color[4] = (isset($color[4]) ? $color[4] : 1) + $amount;
-        $color[4] = min(1, max(0, $color[4]));
-
-        return $color;
-    }
-
-    protected static $libFadeIn = ['color', 'amount'];
-    protected function libFadeIn($args)
-    {
-        return $this->libOpacify($args);
-    }
-
-    // decreases opacity by amount
-    protected static $libTransparentize = ['color', 'amount'];
-    protected function libTransparentize($args)
-    {
-        $color = $this->assertColor($args[0]);
-        $amount = $this->coercePercent($args[1]);
-
-        $color[4] = (isset($color[4]) ? $color[4] : 1) - $amount;
-        $color[4] = min(1, max(0, $color[4]));
-
-        return $color;
-    }
-
-    protected static $libFadeOut = ['color', 'amount'];
-    protected function libFadeOut($args)
-    {
-        return $this->libTransparentize($args);
-    }
-
-    protected static $libUnquote = ['string'];
-    protected function libUnquote($args)
-    {
-        $str = $args[0];
-
-        if ($str[0] === Type::T_STRING) {
-            $str[1] = '';
-        }
-
-        return $str;
-    }
-
-    protected static $libQuote = ['string'];
-    protected function libQuote($args)
-    {
-        $value = $args[0];
-
-        if ($value[0] === Type::T_STRING && ! empty($value[1])) {
-            return $value;
-        }
-
-        return [Type::T_STRING, '"', [$value]];
-    }
-
-    protected static $libPercentage = ['number'];
-    protected function libPercentage($args)
-    {
-        return new Node\Number($this->coercePercent($args[0]) * 100, '%');
-    }
-
-    protected static $libRound = ['number'];
-    protected function libRound($args)
-    {
-        $num = $args[0];
-
-        return new Node\Number(round($num[1]), $num[2]);
-    }
-
-    protected static $libFloor = ['number'];
-    protected function libFloor($args)
-    {
-        $num = $args[0];
-
-        return new Node\Number(floor($num[1]), $num[2]);
-    }
-
-    protected static $libCeil = ['number'];
-    protected function libCeil($args)
-    {
-        $num = $args[0];
-
-        return new Node\Number(ceil($num[1]), $num[2]);
-    }
-
-    protected static $libAbs = ['number'];
-    protected function libAbs($args)
-    {
-        $num = $args[0];
-
-        return new Node\Number(abs($num[1]), $num[2]);
-    }
-
-    protected function libMin($args)
-    {
-        $numbers = $this->getNormalizedNumbers($args);
-        $minOriginal = null;
-        $minNormalized = null;
-
-        foreach ($numbers as $key => $pair) {
-            list($original, $normalized) = $pair;
-
-            if (\is_null($normalized) || \is_null($minNormalized)) {
-                if (\is_null($minOriginal) || $original[1] <= $minOriginal[1]) {
-                    $minOriginal = $original;
-                    $minNormalized = $normalized;
-                }
-            } elseif ($normalized[1] <= $minNormalized[1]) {
-                $minOriginal = $original;
-                $minNormalized = $normalized;
-            }
-        }
-
-        return $minOriginal;
-    }
-
-    protected function libMax($args)
-    {
-        $numbers = $this->getNormalizedNumbers($args);
-        $maxOriginal = null;
-        $maxNormalized = null;
-
-        foreach ($numbers as $key => $pair) {
-            list($original, $normalized) = $pair;
-
-            if (\is_null($normalized) || \is_null($maxNormalized)) {
-                if (\is_null($maxOriginal) || $original[1] >= $maxOriginal[1]) {
-                    $maxOriginal = $original;
-                    $maxNormalized = $normalized;
-                }
-            } elseif ($normalized[1] >= $maxNormalized[1]) {
-                $maxOriginal = $original;
-                $maxNormalized = $normalized;
-            }
-        }
-
-        return $maxOriginal;
-    }
-
-    /**
-     * Helper to normalize args containing numbers
-     *
-     * @param array $args
-     *
-     * @return array
-     */
-    protected function getNormalizedNumbers($args)
-    {
-        $unit         = null;
-        $originalUnit = null;
-        $numbers      = [];
-
-        foreach ($args as $key => $item) {
-            if ($item[0] !== Type::T_NUMBER) {
-                throw $this->error('%s is not a number', $item[0]);
-            }
-
-            $number = $item->normalize();
-
-            if (empty($unit)) {
-                $unit = $number[2];
-                $originalUnit = $item->unitStr();
-            } elseif ($number[1] && $unit !== $number[2] && ! empty($number[2])) {
-                throw $this->error('Incompatible units: "%s" and "%s".', $originalUnit, $item->unitStr());
-            }
-
-            $numbers[$key] = [$args[$key], empty($number[2]) ? null : $number];
-        }
-
-        return $numbers;
-    }
-
-    protected static $libLength = ['list'];
-    protected function libLength($args)
-    {
-        $list = $this->coerceList($args[0], ',', true);
-
-        return \count($list[2]);
-    }
-
-    //protected static $libListSeparator = ['list...'];
-    protected function libListSeparator($args)
-    {
-        if (\count($args) > 1) {
-            return 'comma';
-        }
-
-        $list = $this->coerceList($args[0]);
-
-        if (\count($list[2]) <= 1) {
-            return 'space';
-        }
-
-        if ($list[1] === ',') {
-            return 'comma';
-        }
-
-        return 'space';
-    }
-
-    protected static $libNth = ['list', 'n'];
-    protected function libNth($args)
-    {
-        $list = $this->coerceList($args[0], ',', false);
-        $n = $this->assertNumber($args[1]);
-
-        if ($n > 0) {
-            $n--;
-        } elseif ($n < 0) {
-            $n += \count($list[2]);
-        }
-
-        return isset($list[2][$n]) ? $list[2][$n] : static::$defaultValue;
-    }
-
-    protected static $libSetNth = ['list', 'n', 'value'];
-    protected function libSetNth($args)
-    {
-        $list = $this->coerceList($args[0]);
-        $n = $this->assertNumber($args[1]);
-
-        if ($n > 0) {
-            $n--;
-        } elseif ($n < 0) {
-            $n += \count($list[2]);
-        }
-
-        if (! isset($list[2][$n])) {
-            throw $this->error('Invalid argument for "n"');
-        }
-
-        $list[2][$n] = $args[2];
-
-        return $list;
-    }
-
-    protected static $libMapGet = ['map', 'key'];
-    protected function libMapGet($args)
-    {
-        $map = $this->assertMap($args[0]);
-        $key = $args[1];
-
-        if (! \is_null($key)) {
-            $key = $this->compileStringContent($this->coerceString($key));
-
-            for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
-                if ($key === $this->compileStringContent($this->coerceString($map[1][$i]))) {
-                    return $map[2][$i];
-                }
-            }
-        }
-
-        return static::$null;
-    }
-
-    protected static $libMapKeys = ['map'];
-    protected function libMapKeys($args)
-    {
-        $map = $this->assertMap($args[0]);
-        $keys = $map[1];
-
-        return [Type::T_LIST, ',', $keys];
-    }
-
-    protected static $libMapValues = ['map'];
-    protected function libMapValues($args)
-    {
-        $map = $this->assertMap($args[0]);
-        $values = $map[2];
-
-        return [Type::T_LIST, ',', $values];
-    }
-
-    protected static $libMapRemove = ['map', 'key...'];
-    protected function libMapRemove($args)
-    {
-        $map = $this->assertMap($args[0]);
-        $keyList = $this->assertList($args[1]);
-
-        $keys = [];
-
-        foreach ($keyList[2] as $key) {
-            $keys[] = $this->compileStringContent($this->coerceString($key));
-        }
-
-        for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
-            if (in_array($this->compileStringContent($this->coerceString($map[1][$i])), $keys)) {
-                array_splice($map[1], $i, 1);
-                array_splice($map[2], $i, 1);
-            }
-        }
-
-        return $map;
-    }
-
-    protected static $libMapHasKey = ['map', 'key'];
-    protected function libMapHasKey($args)
-    {
-        $map = $this->assertMap($args[0]);
-        $key = $this->compileStringContent($this->coerceString($args[1]));
-
-        for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
-            if ($key === $this->compileStringContent($this->coerceString($map[1][$i]))) {
-                return true;
-            }
-        }
-
-        return false;
-    }
-
-    protected static $libMapMerge = [
-        ['map1', 'map2'],
-        ['map-1', 'map-2']
-    ];
-    protected function libMapMerge($args)
-    {
-        $map1 = $this->assertMap($args[0]);
-        $map2 = $this->assertMap($args[1]);
-
-        foreach ($map2[1] as $i2 => $key2) {
-            $key = $this->compileStringContent($this->coerceString($key2));
-
-            foreach ($map1[1] as $i1 => $key1) {
-                if ($key === $this->compileStringContent($this->coerceString($key1))) {
-                    $map1[2][$i1] = $map2[2][$i2];
-                    continue 2;
-                }
-            }
-
-            $map1[1][] = $map2[1][$i2];
-            $map1[2][] = $map2[2][$i2];
-        }
-
-        return $map1;
-    }
-
-    protected static $libKeywords = ['args'];
-    protected function libKeywords($args)
-    {
-        $this->assertList($args[0]);
-
-        $keys = [];
-        $values = [];
-
-        foreach ($args[0][2] as $name => $arg) {
-            $keys[] = [Type::T_KEYWORD, $name];
-            $values[] = $arg;
-        }
-
-        return [Type::T_MAP, $keys, $values];
-    }
-
-    protected static $libIsBracketed = ['list'];
-    protected function libIsBracketed($args)
-    {
-        $list = $args[0];
-        $this->coerceList($list, ' ');
-
-        if (! empty($list['enclosing']) && $list['enclosing'] === 'bracket') {
-            return true;
-        }
-
-        return false;
-    }
-
-    protected function listSeparatorForJoin($list1, $sep)
-    {
-        if (! isset($sep)) {
-            return $list1[1];
-        }
-
-        switch ($this->compileValue($sep)) {
-            case 'comma':
-                return ',';
-
-            case 'space':
-                return ' ';
-
-            default:
-                return $list1[1];
-        }
-    }
-
-    protected static $libJoin = ['list1', 'list2', 'separator:null', 'bracketed:auto'];
-    protected function libJoin($args)
-    {
-        list($list1, $list2, $sep, $bracketed) = $args;
-
-        $list1 = $this->coerceList($list1, ' ', true);
-        $list2 = $this->coerceList($list2, ' ', true);
-        $sep   = $this->listSeparatorForJoin($list1, $sep);
-
-        if ($bracketed === static::$true) {
-            $bracketed = true;
-        } elseif ($bracketed === static::$false) {
-            $bracketed = false;
-        } elseif ($bracketed === [Type::T_KEYWORD, 'auto']) {
-            $bracketed = 'auto';
-        } elseif ($bracketed === static::$null) {
-            $bracketed = false;
-        } else {
-            $bracketed = $this->compileValue($bracketed);
-            $bracketed = ! ! $bracketed;
-
-            if ($bracketed === true) {
-                $bracketed = true;
-            }
-        }
-
-        if ($bracketed === 'auto') {
-            $bracketed = false;
-
-            if (! empty($list1['enclosing']) && $list1['enclosing'] === 'bracket') {
-                $bracketed = true;
-            }
-        }
-
-        $res = [Type::T_LIST, $sep, array_merge($list1[2], $list2[2])];
-
-        if (isset($list1['enclosing'])) {
-            $res['enlcosing'] = $list1['enclosing'];
-        }
-
-        if ($bracketed) {
-            $res['enclosing'] = 'bracket';
-        }
-
-        return $res;
-    }
-
-    protected static $libAppend = ['list', 'val', 'separator:null'];
-    protected function libAppend($args)
-    {
-        list($list1, $value, $sep) = $args;
-
-        $list1 = $this->coerceList($list1, ' ', true);
-        $sep   = $this->listSeparatorForJoin($list1, $sep);
-        $res   = [Type::T_LIST, $sep, array_merge($list1[2], [$value])];
-
-        if (isset($list1['enclosing'])) {
-            $res['enclosing'] = $list1['enclosing'];
-        }
-
-        return $res;
-    }
-
-    protected function libZip($args)
-    {
-        foreach ($args as $key => $arg) {
-            $args[$key] = $this->coerceList($arg);
-        }
-
-        $lists = [];
-        $firstList = array_shift($args);
-
-        foreach ($firstList[2] as $key => $item) {
-            $list = [Type::T_LIST, '', [$item]];
-
-            foreach ($args as $arg) {
-                if (isset($arg[2][$key])) {
-                    $list[2][] = $arg[2][$key];
-                } else {
-                    break 2;
-                }
-            }
-
-            $lists[] = $list;
-        }
-
-        return [Type::T_LIST, ',', $lists];
-    }
-
-    protected static $libTypeOf = ['value'];
-    protected function libTypeOf($args)
-    {
-        $value = $args[0];
-
-        switch ($value[0]) {
-            case Type::T_KEYWORD:
-                if ($value === static::$true || $value === static::$false) {
-                    return 'bool';
-                }
-
-                if ($this->coerceColor($value)) {
-                    return 'color';
-                }
-
-                // fall-thru
-            case Type::T_FUNCTION:
-                return 'string';
-
-            case Type::T_FUNCTION_REFERENCE:
-                return 'function';
-
-            case Type::T_LIST:
-                if (isset($value[3]) && $value[3]) {
-                    return 'arglist';
-                }
-
-                // fall-thru
-            default:
-                return $value[0];
-        }
-    }
-
-    protected static $libUnit = ['number'];
-    protected function libUnit($args)
-    {
-        $num = $args[0];
-
-        if ($num[0] === Type::T_NUMBER) {
-            return [Type::T_STRING, '"', [$num->unitStr()]];
-        }
-
-        return '';
-    }
+				$right = \count($right[2]) > 0 ?
+					$whiteRight . $delim . $this->compileValue($right) : '';
+
+				return $left . $this->compileValue($interpolate) . $right;
+
+			case Type::T_INTERPOLATE:
+				// strip quotes if it's a string
+				$reduced = $this->reduce($value[1]);
+
+				switch ($reduced[0]) {
+					case Type::T_LIST:
+						$reduced = $this->extractInterpolation($reduced);
+
+						if ($reduced[0] !== Type::T_LIST) {
+							break;
+						}
+
+						list(, $delim, $items) = $reduced;
+
+						if ($delim !== ' ') {
+							$delim .= ' ';
+						}
+
+						$filtered = [];
+
+						foreach ($items as $item) {
+							if ($item[0] === Type::T_NULL) {
+								continue;
+							}
+
+							$temp = $this->compileValue([Type::T_KEYWORD, $item]);
+
+							if ($temp[0] === Type::T_STRING) {
+								$filtered[] = $this->compileStringContent($temp);
+							} elseif ($temp[0] === Type::T_KEYWORD) {
+								$filtered[] = $temp[1];
+							} else {
+								$filtered[] = $this->compileValue($temp);
+							}
+						}
+
+						$reduced = [Type::T_KEYWORD, implode("$delim", $filtered)];
+						break;
+
+					case Type::T_STRING:
+						$reduced = [Type::T_KEYWORD, $this->compileStringContent($reduced)];
+						break;
+
+					case Type::T_NULL:
+						$reduced = [Type::T_KEYWORD, ''];
+				}
+
+				return $this->compileValue($reduced);
+
+			case Type::T_NULL:
+				return 'null';
+
+			case Type::T_COMMENT:
+				return $this->compileCommentValue($value);
+
+			default:
+				throw $this->error('unknown value type: ' . json_encode($value));
+		}
+	}
+
+	/**
+	 * @param array $value
+	 *
+	 * @return array|string
+	 */
+	protected function compileDebugValue($value)
+	{
+		$value = $this->reduce($value, true);
+
+		switch ($value[0]) {
+			case Type::T_STRING:
+				return $this->compileStringContent($value);
+
+			default:
+				return $this->compileValue($value);
+		}
+	}
+
+	/**
+	 * Flatten list
+	 *
+	 * @param array $list
+	 *
+	 * @return string
+	 */
+	protected function flattenList($list)
+	{
+		return $this->compileValue($list);
+	}
+
+	/**
+	 * Compile string content
+	 *
+	 * @param array $string
+	 *
+	 * @return string
+	 */
+	protected function compileStringContent($string)
+	{
+		$parts = [];
+
+		foreach ($string[2] as $part) {
+			if (\is_array($part) || $part instanceof \ArrayAccess) {
+				$parts[] = $this->compileValue($part);
+			} else {
+				$parts[] = $part;
+			}
+		}
+
+		return implode($parts);
+	}
+
+	/**
+	 * Extract interpolation; it doesn't need to be recursive, compileValue will handle that
+	 *
+	 * @param array $list
+	 *
+	 * @return array
+	 */
+	protected function extractInterpolation($list)
+	{
+		$items = $list[2];
+
+		foreach ($items as $i => $item) {
+			if ($item[0] === Type::T_INTERPOLATE) {
+				$before = [Type::T_LIST, $list[1], \array_slice($items, 0, $i)];
+				$after  = [Type::T_LIST, $list[1], \array_slice($items, $i + 1)];
+
+				return [Type::T_INTERPOLATED, $item, $before, $after];
+			}
+		}
+
+		return $list;
+	}
+
+	/**
+	 * Find the final set of selectors
+	 *
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 * @param \ScssPhp\ScssPhp\Block                $selfParent
+	 *
+	 * @return array
+	 */
+	protected function multiplySelectors(Environment $env, $selfParent = null)
+	{
+		$envs            = $this->compactEnv($env);
+		$selectors       = [];
+		$parentSelectors = [[]];
+
+		$selfParentSelectors = null;
+
+		if (! \is_null($selfParent) && $selfParent->selectors) {
+			$selfParentSelectors = $this->evalSelectors($selfParent->selectors);
+		}
+
+		while ($env = array_pop($envs)) {
+			if (empty($env->selectors)) {
+				continue;
+			}
+
+			$selectors = $env->selectors;
+
+			do {
+				$stillHasSelf  = false;
+				$prevSelectors = $selectors;
+				$selectors     = [];
+
+				foreach ($parentSelectors as $parent) {
+					foreach ($prevSelectors as $selector) {
+						if ($selfParentSelectors) {
+							foreach ($selfParentSelectors as $selfParent) {
+								// if no '&' in the selector, each call will give same result, only add once
+								$s = $this->joinSelectors($parent, $selector, $stillHasSelf, $selfParent);
+								$selectors[serialize($s)] = $s;
+							}
+						} else {
+							$s = $this->joinSelectors($parent, $selector, $stillHasSelf);
+							$selectors[serialize($s)] = $s;
+						}
+					}
+				}
+			} while ($stillHasSelf);
+
+			$parentSelectors = $selectors;
+		}
+
+		$selectors = array_values($selectors);
+
+		// case we are just starting a at-root : nothing to multiply but parentSelectors
+		if (! $selectors && $selfParentSelectors) {
+			$selectors = $selfParentSelectors;
+		}
+
+		return $selectors;
+	}
+
+	/**
+	 * Join selectors; looks for & to replace, or append parent before child
+	 *
+	 * @param array   $parent
+	 * @param array   $child
+	 * @param boolean $stillHasSelf
+	 * @param array   $selfParentSelectors
+	 * @return array
+	 */
+	protected function joinSelectors($parent, $child, &$stillHasSelf, $selfParentSelectors = null)
+	{
+		$setSelf = false;
+		$out = [];
+
+		foreach ($child as $part) {
+			$newPart = [];
+
+			foreach ($part as $p) {
+				// only replace & once and should be recalled to be able to make combinations
+				if ($p === static::$selfSelector && $setSelf) {
+					$stillHasSelf = true;
+				}
+
+				if ($p === static::$selfSelector && ! $setSelf) {
+					$setSelf = true;
+
+					if (\is_null($selfParentSelectors)) {
+						$selfParentSelectors = $parent;
+					}
+
+					foreach ($selfParentSelectors as $i => $parentPart) {
+						if ($i > 0) {
+							$out[] = $newPart;
+							$newPart = [];
+						}
+
+						foreach ($parentPart as $pp) {
+							if (\is_array($pp)) {
+								$flatten = [];
+
+								array_walk_recursive($pp, function ($a) use (&$flatten) {
+									$flatten[] = $a;
+								});
+
+								$pp = implode($flatten);
+							}
+
+							$newPart[] = $pp;
+						}
+					}
+				} else {
+					$newPart[] = $p;
+				}
+			}
+
+			$out[] = $newPart;
+		}
+
+		return $setSelf ? $out : array_merge($parent, $child);
+	}
+
+	/**
+	 * Multiply media
+	 *
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 * @param array                                 $childQueries
+	 *
+	 * @return array
+	 */
+	protected function multiplyMedia(Environment $env = null, $childQueries = null)
+	{
+		if (
+			! isset($env) ||
+			! empty($env->block->type) && $env->block->type !== Type::T_MEDIA
+		) {
+			return $childQueries;
+		}
+
+		// plain old block, skip
+		if (empty($env->block->type)) {
+			return $this->multiplyMedia($env->parent, $childQueries);
+		}
+
+		$parentQueries = isset($env->block->queryList)
+			? $env->block->queryList
+			: [[[Type::T_MEDIA_VALUE, $env->block->value]]];
+
+		$store = [$this->env, $this->storeEnv];
+
+		$this->env      = $env;
+		$this->storeEnv = null;
+		$parentQueries  = $this->evaluateMediaQuery($parentQueries);
+
+		list($this->env, $this->storeEnv) = $store;
+
+		if (\is_null($childQueries)) {
+			$childQueries = $parentQueries;
+		} else {
+			$originalQueries = $childQueries;
+			$childQueries = [];
+
+			foreach ($parentQueries as $parentQuery) {
+				foreach ($originalQueries as $childQuery) {
+					$childQueries[] = array_merge(
+						$parentQuery,
+						[[Type::T_MEDIA_TYPE, [Type::T_KEYWORD, 'all']]],
+						$childQuery
+					);
+				}
+			}
+		}
+
+		return $this->multiplyMedia($env->parent, $childQueries);
+	}
+
+	/**
+	 * Convert env linked list to stack
+	 *
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 *
+	 * @return array
+	 */
+	protected function compactEnv(Environment $env)
+	{
+		for ($envs = []; $env; $env = $env->parent) {
+			$envs[] = $env;
+		}
+
+		return $envs;
+	}
+
+	/**
+	 * Convert env stack to singly linked list
+	 *
+	 * @param array $envs
+	 *
+	 * @return \ScssPhp\ScssPhp\Compiler\Environment
+	 */
+	protected function extractEnv($envs)
+	{
+		for ($env = null; $e = array_pop($envs);) {
+			$e->parent = $env;
+			$env = $e;
+		}
+
+		return $env;
+	}
+
+	/**
+	 * Push environment
+	 *
+	 * @param \ScssPhp\ScssPhp\Block $block
+	 *
+	 * @return \ScssPhp\ScssPhp\Compiler\Environment
+	 */
+	protected function pushEnv(Block $block = null)
+	{
+		$env = new Environment();
+		$env->parent = $this->env;
+		$env->parentStore = $this->storeEnv;
+		$env->store  = [];
+		$env->block  = $block;
+		$env->depth  = isset($this->env->depth) ? $this->env->depth + 1 : 0;
+
+		$this->env = $env;
+		$this->storeEnv = null;
+
+		return $env;
+	}
+
+	/**
+	 * Pop environment
+	 */
+	protected function popEnv()
+	{
+		$this->storeEnv = $this->env->parentStore;
+		$this->env = $this->env->parent;
+	}
+
+	/**
+	 * Propagate vars from a just poped Env (used in @each and @for)
+	 *
+	 * @param array      $store
+	 * @param null|array $excludedVars
+	 */
+	protected function backPropagateEnv($store, $excludedVars = null)
+	{
+		foreach ($store as $key => $value) {
+			if (empty($excludedVars) || ! \in_array($key, $excludedVars)) {
+				$this->set($key, $value, true);
+			}
+		}
+	}
+
+	/**
+	 * Get store environment
+	 *
+	 * @return \ScssPhp\ScssPhp\Compiler\Environment
+	 */
+	protected function getStoreEnv()
+	{
+		return isset($this->storeEnv) ? $this->storeEnv : $this->env;
+	}
+
+	/**
+	 * Set variable
+	 *
+	 * @param string                                $name
+	 * @param mixed                                 $value
+	 * @param boolean                               $shadow
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 * @param mixed                                 $valueUnreduced
+	 */
+	protected function set($name, $value, $shadow = false, Environment $env = null, $valueUnreduced = null)
+	{
+		$name = $this->normalizeName($name);
+
+		if (! isset($env)) {
+			$env = $this->getStoreEnv();
+		}
+
+		if ($shadow) {
+			$this->setRaw($name, $value, $env, $valueUnreduced);
+		} else {
+			$this->setExisting($name, $value, $env, $valueUnreduced);
+		}
+	}
+
+	/**
+	 * Set existing variable
+	 *
+	 * @param string                                $name
+	 * @param mixed                                 $value
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 * @param mixed                                 $valueUnreduced
+	 */
+	protected function setExisting($name, $value, Environment $env, $valueUnreduced = null)
+	{
+		$storeEnv = $env;
+		$specialContentKey = static::$namespaces['special'] . 'content';
+
+		$hasNamespace = $name[0] === '^' || $name[0] === '@' || $name[0] === '%';
+
+		$maxDepth = 10000;
+
+		for (;;) {
+			if ($maxDepth-- <= 0) {
+				break;
+			}
+
+			if (\array_key_exists($name, $env->store)) {
+				break;
+			}
+
+			if (! $hasNamespace && isset($env->marker)) {
+				if (! empty($env->store[$specialContentKey])) {
+					$env = $env->store[$specialContentKey]->scope;
+					continue;
+				}
+
+				if (! empty($env->declarationScopeParent)) {
+					$env = $env->declarationScopeParent;
+					continue;
+				} else {
+					$env = $storeEnv;
+					break;
+				}
+			}
+
+			if (isset($env->parentStore)) {
+				$env = $env->parentStore;
+			} elseif (isset($env->parent)) {
+				$env = $env->parent;
+			} else {
+				$env = $storeEnv;
+				break;
+			}
+		}
+
+		$env->store[$name] = $value;
+
+		if ($valueUnreduced) {
+			$env->storeUnreduced[$name] = $valueUnreduced;
+		}
+	}
+
+	/**
+	 * Set raw variable
+	 *
+	 * @param string                                $name
+	 * @param mixed                                 $value
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 * @param mixed                                 $valueUnreduced
+	 */
+	protected function setRaw($name, $value, Environment $env, $valueUnreduced = null)
+	{
+		$env->store[$name] = $value;
+
+		if ($valueUnreduced) {
+			$env->storeUnreduced[$name] = $valueUnreduced;
+		}
+	}
+
+	/**
+	 * Get variable
+	 *
+	 * @api
+	 *
+	 * @param string                                $name
+	 * @param boolean                               $shouldThrow
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 * @param boolean                               $unreduced
+	 *
+	 * @return mixed|null
+	 */
+	public function get($name, $shouldThrow = true, Environment $env = null, $unreduced = false)
+	{
+		$normalizedName = $this->normalizeName($name);
+		$specialContentKey = static::$namespaces['special'] . 'content';
+
+		if (! isset($env)) {
+			$env = $this->getStoreEnv();
+		}
+
+		$hasNamespace = $normalizedName[0] === '^' || $normalizedName[0] === '@' || $normalizedName[0] === '%';
+
+		$maxDepth = 10000;
+
+		for (;;) {
+			if ($maxDepth-- <= 0) {
+				break;
+			}
+
+			if (\array_key_exists($normalizedName, $env->store)) {
+				if ($unreduced && isset($env->storeUnreduced[$normalizedName])) {
+					return $env->storeUnreduced[$normalizedName];
+				}
+
+				return $env->store[$normalizedName];
+			}
+
+			if (! $hasNamespace && isset($env->marker)) {
+				if (! empty($env->store[$specialContentKey])) {
+					$env = $env->store[$specialContentKey]->scope;
+					continue;
+				}
+
+				if (! empty($env->declarationScopeParent)) {
+					$env = $env->declarationScopeParent;
+				} else {
+					$env = $this->rootEnv;
+				}
+				continue;
+			}
+
+			if (isset($env->parentStore)) {
+				$env = $env->parentStore;
+			} elseif (isset($env->parent)) {
+				$env = $env->parent;
+			} else {
+				break;
+			}
+		}
+
+		if ($shouldThrow) {
+			throw $this->error("Undefined variable \$$name" . ($maxDepth <= 0 ? ' (infinite recursion)' : ''));
+		}
+
+		// found nothing
+		return null;
+	}
+
+	/**
+	 * Has variable?
+	 *
+	 * @param string                                $name
+	 * @param \ScssPhp\ScssPhp\Compiler\Environment $env
+	 *
+	 * @return boolean
+	 */
+	protected function has($name, Environment $env = null)
+	{
+		return ! \is_null($this->get($name, false, $env));
+	}
+
+	/**
+	 * Inject variables
+	 *
+	 * @param array $args
+	 */
+	protected function injectVariables(array $args)
+	{
+		if (empty($args)) {
+			return;
+		}
+
+		$parser = $this->parserFactory(__METHOD__);
+
+		foreach ($args as $name => $strValue) {
+			if ($name[0] === '$') {
+				$name = substr($name, 1);
+			}
+
+			if (! $parser->parseValue($strValue, $value)) {
+				$value = $this->coerceValue($strValue);
+			}
+
+			$this->set($name, $value);
+		}
+	}
+
+	/**
+	 * Set variables
+	 *
+	 * @api
+	 *
+	 * @param array $variables
+	 */
+	public function setVariables(array $variables)
+	{
+		$this->registeredVars = array_merge($this->registeredVars, $variables);
+	}
+
+	/**
+	 * Unset variable
+	 *
+	 * @api
+	 *
+	 * @param string $name
+	 */
+	public function unsetVariable($name)
+	{
+		unset($this->registeredVars[$name]);
+	}
+
+	/**
+	 * Returns list of variables
+	 *
+	 * @api
+	 *
+	 * @return array
+	 */
+	public function getVariables()
+	{
+		return $this->registeredVars;
+	}
+
+	/**
+	 * Adds to list of parsed files
+	 *
+	 * @api
+	 *
+	 * @param string $path
+	 */
+	public function addParsedFile($path)
+	{
+		if (isset($path) && is_file($path)) {
+			$this->parsedFiles[realpath($path)] = filemtime($path);
+		}
+	}
+
+	/**
+	 * Returns list of parsed files
+	 *
+	 * @api
+	 *
+	 * @return array
+	 */
+	public function getParsedFiles()
+	{
+		return $this->parsedFiles;
+	}
+
+	/**
+	 * Add import path
+	 *
+	 * @api
+	 *
+	 * @param string|callable $path
+	 */
+	public function addImportPath($path)
+	{
+		if (! \in_array($path, $this->importPaths)) {
+			$this->importPaths[] = $path;
+		}
+	}
+
+	/**
+	 * Set import paths
+	 *
+	 * @api
+	 *
+	 * @param string|array $path
+	 */
+	public function setImportPaths($path)
+	{
+		$this->importPaths = (array) $path;
+	}
+
+	/**
+	 * Set number precision
+	 *
+	 * @api
+	 *
+	 * @param integer $numberPrecision
+	 *
+	 * @deprecated The number precision is not configurable anymore. The default is enough for all browsers.
+	 */
+	public function setNumberPrecision($numberPrecision)
+	{
+		@trigger_error('The number precision is not configurable anymore. '
+			. 'The default is enough for all browsers.', E_USER_DEPRECATED);
+	}
+
+	/**
+	 * Set formatter
+	 *
+	 * @api
+	 *
+	 * @param string $formatterName
+	 */
+	public function setFormatter($formatterName)
+	{
+		$this->formatter = $formatterName;
+	}
+
+	/**
+	 * Set line number style
+	 *
+	 * @api
+	 *
+	 * @param string $lineNumberStyle
+	 */
+	public function setLineNumberStyle($lineNumberStyle)
+	{
+		$this->lineNumberStyle = $lineNumberStyle;
+	}
+
+	/**
+	 * Enable/disable source maps
+	 *
+	 * @api
+	 *
+	 * @param integer $sourceMap
+	 */
+	public function setSourceMap($sourceMap)
+	{
+		$this->sourceMap = $sourceMap;
+	}
+
+	/**
+	 * Set source map options
+	 *
+	 * @api
+	 *
+	 * @param array $sourceMapOptions
+	 */
+	public function setSourceMapOptions($sourceMapOptions)
+	{
+		$this->sourceMapOptions = $sourceMapOptions;
+	}
+
+	/**
+	 * Register function
+	 *
+	 * @api
+	 *
+	 * @param string   $name
+	 * @param callable $func
+	 * @param array    $prototype
+	 */
+	public function registerFunction($name, $func, $prototype = null)
+	{
+		$this->userFunctions[$this->normalizeName($name)] = [$func, $prototype];
+	}
+
+	/**
+	 * Unregister function
+	 *
+	 * @api
+	 *
+	 * @param string $name
+	 */
+	public function unregisterFunction($name)
+	{
+		unset($this->userFunctions[$this->normalizeName($name)]);
+	}
+
+	/**
+	 * Add feature
+	 *
+	 * @api
+	 *
+	 * @param string $name
+	 */
+	public function addFeature($name)
+	{
+		$this->registeredFeatures[$name] = true;
+	}
+
+	/**
+	 * Import file
+	 *
+	 * @param string                                 $path
+	 * @param \ScssPhp\ScssPhp\Formatter\OutputBlock $out
+	 */
+	protected function importFile($path, OutputBlock $out)
+	{
+		$this->pushCallStack('import ' . $path);
+		// see if tree is cached
+		$realPath = realpath($path);
+
+		if (isset($this->importCache[$realPath])) {
+			$this->handleImportLoop($realPath);
+
+			$tree = $this->importCache[$realPath];
+		} else {
+			$code   = file_get_contents($path);
+			$parser = $this->parserFactory($path);
+			$tree   = $parser->parse($code);
+
+			$this->importCache[$realPath] = $tree;
+		}
+
+		$pi = pathinfo($path);
+
+		array_unshift($this->importPaths, $pi['dirname']);
+		$this->compileChildrenNoReturn($tree->children, $out);
+		array_shift($this->importPaths);
+		$this->popCallStack();
+	}
+
+	/**
+	 * Return the file path for an import url if it exists
+	 *
+	 * @api
+	 *
+	 * @param string $url
+	 *
+	 * @return string|null
+	 */
+	public function findImport($url)
+	{
+		$urls = [];
+
+		$hasExtension = preg_match('/[.]s?css$/', $url);
+
+		// for "normal" scss imports (ignore vanilla css and external requests)
+		if (! preg_match('~\.css$|^https?://|^//~', $url)) {
+			$isPartial = (strpos(basename($url), '_') === 0);
+
+			// try both normal and the _partial filename
+			$urls = [$url . ($hasExtension ? '' : '.scss')];
+
+			if (! $isPartial) {
+				$urls[] = preg_replace('~[^/]+$~', '_\0', $url) . ($hasExtension ? '' : '.scss');
+			}
+
+			if (! $hasExtension) {
+				$urls[] = "$url/index.scss";
+				$urls[] = "$url/_index.scss";
+				// allow to find a plain css file, *if* no scss or partial scss is found
+				$urls[] .= $url . '.css';
+			}
+		}
+
+		foreach ($this->importPaths as $dir) {
+			if (\is_string($dir)) {
+				// check urls for normal import paths
+				foreach ($urls as $full) {
+					$separator = (
+						! empty($dir) &&
+						substr($dir, -1) !== '/' &&
+						substr($full, 0, 1) !== '/'
+					) ? '/' : '';
+					$full = $dir . $separator . $full;
+
+					if (is_file($file = $full)) {
+						return $file;
+					}
+				}
+			} elseif (\is_callable($dir)) {
+				// check custom callback for import path
+				$file = \call_user_func($dir, $url);
+
+				if (! \is_null($file)) {
+					return $file;
+				}
+			}
+		}
+
+		if ($urls) {
+			if (! $hasExtension || preg_match('/[.]scss$/', $url)) {
+				throw $this->error("`$url` file not found for @import");
+			}
+		}
+
+		return null;
+	}
+
+	/**
+	 * Set encoding
+	 *
+	 * @api
+	 *
+	 * @param string $encoding
+	 */
+	public function setEncoding($encoding)
+	{
+		$this->encoding = $encoding;
+	}
+
+	/**
+	 * Ignore errors?
+	 *
+	 * @api
+	 *
+	 * @param boolean $ignoreErrors
+	 *
+	 * @return \ScssPhp\ScssPhp\Compiler
+	 *
+	 * @deprecated Ignoring Sass errors is not longer supported.
+	 */
+	public function setIgnoreErrors($ignoreErrors)
+	{
+		@trigger_error('Ignoring Sass errors is not longer supported.', E_USER_DEPRECATED);
+
+		return $this;
+	}
+
+	/**
+	 * Get source position
+	 *
+	 * @api
+	 *
+	 * @return array
+	 */
+	public function getSourcePosition()
+	{
+		$sourceFile = isset($this->sourceNames[$this->sourceIndex]) ? $this->sourceNames[$this->sourceIndex] : '';
+
+		return [$sourceFile, $this->sourceLine, $this->sourceColumn];
+	}
+
+	/**
+	 * Throw error (exception)
+	 *
+	 * @api
+	 *
+	 * @param string $msg Message with optional sprintf()-style vararg parameters
+	 *
+	 * @throws \ScssPhp\ScssPhp\Exception\CompilerException
+	 *
+	 * @deprecated use "error" and throw the exception in the caller instead.
+	 */
+	public function throwError($msg)
+	{
+		@trigger_error(
+			'The method "throwError" is deprecated. Use "error" and throw the exception in the caller instead',
+			E_USER_DEPRECATED
+		);
+
+		throw $this->error(...func_get_args());
+	}
+
+	/**
+	 * Build an error (exception)
+	 *
+	 * @api
+	 *
+	 * @param string $msg Message with optional sprintf()-style vararg parameters
+	 *
+	 * @return CompilerException
+	 */
+	public function error($msg, ...$args)
+	{
+		if ($args) {
+			$msg = sprintf($msg, ...$args);
+		}
+
+		if (! $this->ignoreCallStackMessage) {
+			$line   = $this->sourceLine;
+			$column = $this->sourceColumn;
+
+			$loc = isset($this->sourceNames[$this->sourceIndex])
+				? $this->sourceNames[$this->sourceIndex] . " on line $line, at column $column"
+				: "line: $line, column: $column";
+
+			$msg = "$msg: $loc";
+
+			$callStackMsg = $this->callStackMessage();
+
+			if ($callStackMsg) {
+				$msg .= "\nCall Stack:\n" . $callStackMsg;
+			}
+		}
+
+		return new CompilerException($msg);
+	}
+
+	/**
+	 * @param string $functionName
+	 * @param array $ExpectedArgs
+	 * @param int $nbActual
+	 * @return CompilerException
+	 */
+	public function errorArgsNumber($functionName, $ExpectedArgs, $nbActual)
+	{
+		$nbExpected = \count($ExpectedArgs);
+
+		if ($nbActual > $nbExpected) {
+			return $this->error(
+				'Error: Only %d arguments allowed in %s(), but %d were passed.',
+				$nbExpected,
+				$functionName,
+				$nbActual
+			);
+		} else {
+			$missing = [];
+
+			while (count($ExpectedArgs) && count($ExpectedArgs) > $nbActual) {
+				array_unshift($missing, array_pop($ExpectedArgs));
+			}
+
+			return $this->error(
+				'Error: %s() argument%s %s missing.',
+				$functionName,
+				count($missing) > 1 ? 's' : '',
+				implode(', ', $missing)
+			);
+		}
+	}
+
+	/**
+	 * Beautify call stack for output
+	 *
+	 * @param boolean $all
+	 * @param null    $limit
+	 *
+	 * @return string
+	 */
+	protected function callStackMessage($all = false, $limit = null)
+	{
+		$callStackMsg = [];
+		$ncall = 0;
+
+		if ($this->callStack) {
+			foreach (array_reverse($this->callStack) as $call) {
+				if ($all || (isset($call['n']) && $call['n'])) {
+					$msg = '#' . $ncall++ . ' ' . $call['n'] . ' ';
+					$msg .= (isset($this->sourceNames[$call[Parser::SOURCE_INDEX]])
+						  ? $this->sourceNames[$call[Parser::SOURCE_INDEX]]
+						  : '(unknown file)');
+					$msg .= ' on line ' . $call[Parser::SOURCE_LINE];
+
+					$callStackMsg[] = $msg;
+
+					if (! \is_null($limit) && $ncall > $limit) {
+						break;
+					}
+				}
+			}
+		}
+
+		return implode("\n", $callStackMsg);
+	}
+
+	/**
+	 * Handle import loop
+	 *
+	 * @param string $name
+	 *
+	 * @throws \Exception
+	 */
+	protected function handleImportLoop($name)
+	{
+		for ($env = $this->env; $env; $env = $env->parent) {
+			if (! $env->block) {
+				continue;
+			}
+
+			$file = $this->sourceNames[$env->block->sourceIndex];
+
+			if (realpath($file) === $name) {
+				throw $this->error('An @import loop has been found: %s imports %s', $file, basename($file));
+			}
+		}
+	}
+
+	/**
+	 * Call SCSS @function
+	 *
+	 * @param Object $func
+	 * @param array  $argValues
+	 *
+	 * @return array $returnValue
+	 */
+	protected function callScssFunction($func, $argValues)
+	{
+		if (! $func) {
+			return static::$defaultValue;
+		}
+		$name = $func->name;
+
+		$this->pushEnv();
+
+		// set the args
+		if (isset($func->args)) {
+			$this->applyArguments($func->args, $argValues);
+		}
+
+		// throw away lines and children
+		$tmp = new OutputBlock();
+		$tmp->lines    = [];
+		$tmp->children = [];
+
+		$this->env->marker = 'function';
+
+		if (! empty($func->parentEnv)) {
+			$this->env->declarationScopeParent = $func->parentEnv;
+		} else {
+			throw $this->error("@function $name() without parentEnv");
+		}
+
+		$ret = $this->compileChildren($func->children, $tmp, $this->env->marker . ' ' . $name);
+
+		$this->popEnv();
+
+		return ! isset($ret) ? static::$defaultValue : $ret;
+	}
+
+	/**
+	 * Call built-in and registered (PHP) functions
+	 *
+	 * @param string $name
+	 * @param string|array $function
+	 * @param array  $prototype
+	 * @param array  $args
+	 *
+	 * @return array
+	 */
+	protected function callNativeFunction($name, $function, $prototype, $args)
+	{
+		$libName = (is_array($function) ? end($function) : null);
+		$sorted_kwargs = $this->sortNativeFunctionArgs($libName, $prototype, $args);
+
+		if (\is_null($sorted_kwargs)) {
+			return null;
+		}
+		@list($sorted, $kwargs) = $sorted_kwargs;
+
+		if ($name !== 'if' && $name !== 'call') {
+			$inExp = true;
+
+			if ($name === 'join') {
+				$inExp = false;
+			}
+
+			foreach ($sorted as &$val) {
+				$val = $this->reduce($val, $inExp);
+			}
+		}
+
+		$returnValue = \call_user_func($function, $sorted, $kwargs);
+
+		if (! isset($returnValue)) {
+			return null;
+		}
+
+		return $this->coerceValue($returnValue);
+	}
+
+	/**
+	 * Get built-in function
+	 *
+	 * @param string $name Normalized name
+	 *
+	 * @return array
+	 */
+	protected function getBuiltinFunction($name)
+	{
+		$libName = 'lib' . preg_replace_callback(
+			'/_(.)/',
+			function ($m) {
+				return ucfirst($m[1]);
+			},
+			ucfirst($name)
+		);
+
+		return [$this, $libName];
+	}
+
+	/**
+	 * Sorts keyword arguments
+	 *
+	 * @param string $functionName
+	 * @param array  $prototypes
+	 * @param array  $args
+	 *
+	 * @return array|null
+	 */
+	protected function sortNativeFunctionArgs($functionName, $prototypes, $args)
+	{
+		static $parser = null;
+
+		if (! isset($prototypes)) {
+			$keyArgs = [];
+			$posArgs = [];
+
+			if (\is_array($args) && \count($args) && \end($args) === static::$null) {
+				array_pop($args);
+			}
+
+			// separate positional and keyword arguments
+			foreach ($args as $arg) {
+				list($key, $value) = $arg;
+
+				if (empty($key) or empty($key[1])) {
+					$posArgs[] = empty($arg[2]) ? $value : $arg;
+				} else {
+					$keyArgs[$key[1]] = $value;
+				}
+			}
+
+			return [$posArgs, $keyArgs];
+		}
+
+		// specific cases ?
+		if (\in_array($functionName, ['libRgb', 'libRgba', 'libHsl', 'libHsla'])) {
+			// notation 100 127 255 / 0 is in fact a simple list of 4 values
+			foreach ($args as $k => $arg) {
+				if ($arg[1][0] === Type::T_LIST && \count($arg[1][2]) === 3) {
+					$last = end($arg[1][2]);
+
+					if ($last[0] === Type::T_EXPRESSION && $last[1] === '/') {
+						array_pop($arg[1][2]);
+						$arg[1][2][] = $last[2];
+						$arg[1][2][] = $last[3];
+						$args[$k] = $arg;
+					}
+				}
+			}
+		}
+
+		$finalArgs = [];
+
+		if (! \is_array(reset($prototypes))) {
+			$prototypes = [$prototypes];
+		}
+
+		$keyArgs = [];
+
+		// trying each prototypes
+		$prototypeHasMatch = false;
+		$exceptionMessage = '';
+
+		foreach ($prototypes as $prototype) {
+			$argDef = [];
+
+			foreach ($prototype as $i => $p) {
+				$default = null;
+				$p       = explode(':', $p, 2);
+				$name    = array_shift($p);
+
+				if (\count($p)) {
+					$p = trim(reset($p));
+
+					if ($p === 'null') {
+						// differentiate this null from the static::$null
+						$default = [Type::T_KEYWORD, 'null'];
+					} else {
+						if (\is_null($parser)) {
+							$parser = $this->parserFactory(__METHOD__);
+						}
+
+						$parser->parseValue($p, $default);
+					}
+				}
+
+				$isVariable = false;
+
+				if (substr($name, -3) === '...') {
+					$isVariable = true;
+					$name = substr($name, 0, -3);
+				}
+
+				$argDef[] = [$name, $default, $isVariable];
+			}
+
+			$ignoreCallStackMessage = $this->ignoreCallStackMessage;
+			$this->ignoreCallStackMessage = true;
+
+			try {
+				if (\count($args) > \count($argDef)) {
+					$lastDef = end($argDef);
+
+					// check that last arg is not a ...
+					if (empty($lastDef[2])) {
+						throw $this->errorArgsNumber($functionName, $argDef, \count($args));
+					}
+				}
+				$vars = $this->applyArguments($argDef, $args, false, false);
+
+				// ensure all args are populated
+				foreach ($prototype as $i => $p) {
+					$name = explode(':', $p)[0];
+
+					if (! isset($finalArgs[$i])) {
+						$finalArgs[$i] = null;
+					}
+				}
+
+				// apply positional args
+				foreach (array_values($vars) as $i => $val) {
+					$finalArgs[$i] = $val;
+				}
+
+				$keyArgs = array_merge($keyArgs, $vars);
+				$prototypeHasMatch = true;
+
+				// overwrite positional args with keyword args
+				foreach ($prototype as $i => $p) {
+					$name = explode(':', $p)[0];
+
+					if (isset($keyArgs[$name])) {
+						$finalArgs[$i] = $keyArgs[$name];
+					}
+
+					// special null value as default: translate to real null here
+					if ($finalArgs[$i] === [Type::T_KEYWORD, 'null']) {
+						$finalArgs[$i] = null;
+					}
+				}
+				// should we break if this prototype seems fulfilled?
+			} catch (CompilerException $e) {
+				$exceptionMessage = $e->getMessage();
+			}
+			$this->ignoreCallStackMessage = $ignoreCallStackMessage;
+		}
+
+		if ($exceptionMessage && ! $prototypeHasMatch) {
+			if (\in_array($functionName, ['libRgb', 'libRgba', 'libHsl', 'libHsla'])) {
+				// if var() or calc() is used as an argument, return as a css function
+				foreach ($args as $arg) {
+					if ($arg[1][0] === Type::T_FUNCTION_CALL && in_array($arg[1][1], ['var'])) {
+						return null;
+					}
+				}
+			}
+
+			throw $this->error($exceptionMessage);
+		}
+
+		return [$finalArgs, $keyArgs];
+	}
+
+	/**
+	 * Apply argument values per definition
+	 *
+	 * @param array   $argDef
+	 * @param array   $argValues
+	 * @param boolean $storeInEnv
+	 * @param boolean $reduce
+	 *   only used if $storeInEnv = false
+	 *
+	 * @return array
+	 *
+	 * @throws \Exception
+	 */
+	protected function applyArguments($argDef, $argValues, $storeInEnv = true, $reduce = true)
+	{
+		$output = [];
+
+		if (\is_array($argValues) && \count($argValues) && end($argValues) === static::$null) {
+			array_pop($argValues);
+		}
+
+		if ($storeInEnv) {
+			$storeEnv = $this->getStoreEnv();
+
+			$env = new Environment();
+			$env->store = $storeEnv->store;
+		}
+
+		$hasVariable = false;
+		$args = [];
+
+		foreach ($argDef as $i => $arg) {
+			list($name, $default, $isVariable) = $argDef[$i];
+
+			$args[$name] = [$i, $name, $default, $isVariable];
+			$hasVariable |= $isVariable;
+		}
+
+		$splatSeparator      = null;
+		$keywordArgs         = [];
+		$deferredKeywordArgs = [];
+		$deferredNamedKeywordArgs = [];
+		$remaining           = [];
+		$hasKeywordArgument  = false;
+
+		// assign the keyword args
+		foreach ((array) $argValues as $arg) {
+			if (! empty($arg[0])) {
+				$hasKeywordArgument = true;
+
+				$name = $arg[0][1];
+
+				if (! isset($args[$name])) {
+					foreach (array_keys($args) as $an) {
+						if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
+							$name = $an;
+							break;
+						}
+					}
+				}
+
+				if (! isset($args[$name]) || $args[$name][3]) {
+					if ($hasVariable) {
+						$deferredNamedKeywordArgs[$name] = $arg[1];
+					} else {
+						throw $this->error("Mixin or function doesn't have an argument named $%s.", $arg[0][1]);
+					}
+				} elseif ($args[$name][0] < \count($remaining)) {
+					throw $this->error("The argument $%s was passed both by position and by name.", $arg[0][1]);
+				} else {
+					$keywordArgs[$name] = $arg[1];
+				}
+			} elseif (! empty($arg[2])) {
+				// $arg[2] means a var followed by ... in the arg ($list... )
+				$val = $this->reduce($arg[1], true);
+
+				if ($val[0] === Type::T_LIST) {
+					foreach ($val[2] as $name => $item) {
+						if (! is_numeric($name)) {
+							if (! isset($args[$name])) {
+								foreach (array_keys($args) as $an) {
+									if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
+										$name = $an;
+										break;
+									}
+								}
+							}
+
+							if ($hasVariable) {
+								$deferredKeywordArgs[$name] = $item;
+							} else {
+								$keywordArgs[$name] = $item;
+							}
+						} else {
+							if (\is_null($splatSeparator)) {
+								$splatSeparator = $val[1];
+							}
+
+							$remaining[] = $item;
+						}
+					}
+				} elseif ($val[0] === Type::T_MAP) {
+					foreach ($val[1] as $i => $name) {
+						$name = $this->compileStringContent($this->coerceString($name));
+						$item = $val[2][$i];
+
+						if (! is_numeric($name)) {
+							if (! isset($args[$name])) {
+								foreach (array_keys($args) as $an) {
+									if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
+										$name = $an;
+										break;
+									}
+								}
+							}
+
+							if ($hasVariable) {
+								$deferredKeywordArgs[$name] = $item;
+							} else {
+								$keywordArgs[$name] = $item;
+							}
+						} else {
+							if (\is_null($splatSeparator)) {
+								$splatSeparator = $val[1];
+							}
+
+							$remaining[] = $item;
+						}
+					}
+				} else {
+					$remaining[] = $val;
+				}
+			} elseif ($hasKeywordArgument) {
+				throw $this->error('Positional arguments must come before keyword arguments.');
+			} else {
+				$remaining[] = $arg[1];
+			}
+		}
+
+		foreach ($args as $arg) {
+			list($i, $name, $default, $isVariable) = $arg;
+
+			if ($isVariable) {
+				// only if more than one arg : can not be passed as position and value
+				// see https://github.com/sass/libsass/issues/2927
+				if (count($args) > 1) {
+					if (isset($remaining[$i]) && isset($deferredNamedKeywordArgs[$name])) {
+						throw $this->error("The argument $%s was passed both by position and by name.", $name);
+					}
+				}
+
+				$val = [Type::T_LIST, \is_null($splatSeparator) ? ',' : $splatSeparator , [], $isVariable];
+
+				for ($count = \count($remaining); $i < $count; $i++) {
+					$val[2][] = $remaining[$i];
+				}
+
+				foreach ($deferredKeywordArgs as $itemName => $item) {
+					$val[2][$itemName] = $item;
+				}
+
+				foreach ($deferredNamedKeywordArgs as $itemName => $item) {
+					$val[2][$itemName] = $item;
+				}
+			} elseif (isset($remaining[$i])) {
+				$val = $remaining[$i];
+			} elseif (isset($keywordArgs[$name])) {
+				$val = $keywordArgs[$name];
+			} elseif (! empty($default)) {
+				continue;
+			} else {
+				throw $this->error("Missing argument $name");
+			}
+
+			if ($storeInEnv) {
+				$this->set($name, $this->reduce($val, true), true, $env);
+			} else {
+				$output[$name] = ($reduce ? $this->reduce($val, true) : $val);
+			}
+		}
+
+		if ($storeInEnv) {
+			$storeEnv->store = $env->store;
+		}
+
+		foreach ($args as $arg) {
+			list($i, $name, $default, $isVariable) = $arg;
+
+			if ($isVariable || isset($remaining[$i]) || isset($keywordArgs[$name]) || empty($default)) {
+				continue;
+			}
+
+			if ($storeInEnv) {
+				$this->set($name, $this->reduce($default, true), true);
+			} else {
+				$output[$name] = ($reduce ? $this->reduce($default, true) : $default);
+			}
+		}
+
+		return $output;
+	}
+
+	/**
+	 * Coerce a php value into a scss one
+	 *
+	 * @param mixed $value
+	 *
+	 * @return array|\ScssPhp\ScssPhp\Node\Number
+	 */
+	protected function coerceValue($value)
+	{
+		if (\is_array($value) || $value instanceof \ArrayAccess) {
+			return $value;
+		}
+
+		if (\is_bool($value)) {
+			return $this->toBool($value);
+		}
+
+		if (\is_null($value)) {
+			return static::$null;
+		}
+
+		if (is_numeric($value)) {
+			return new Node\Number($value, '');
+		}
+
+		if ($value === '') {
+			return static::$emptyString;
+		}
+
+		$value = [Type::T_KEYWORD, $value];
+		$color = $this->coerceColor($value);
+
+		if ($color) {
+			return $color;
+		}
+
+		return $value;
+	}
+
+	/**
+	 * Coerce something to map
+	 *
+	 * @param array $item
+	 *
+	 * @return array
+	 */
+	protected function coerceMap($item)
+	{
+		if ($item[0] === Type::T_MAP) {
+			return $item;
+		}
+
+		if (
+			$item[0] === static::$emptyList[0] &&
+			$item[1] === static::$emptyList[1] &&
+			$item[2] === static::$emptyList[2]
+		) {
+			return static::$emptyMap;
+		}
+
+		return $item;
+	}
+
+	/**
+	 * Coerce something to list
+	 *
+	 * @param array   $item
+	 * @param string  $delim
+	 * @param boolean $removeTrailingNull
+	 *
+	 * @return array
+	 */
+	protected function coerceList($item, $delim = ',', $removeTrailingNull = false)
+	{
+		if (isset($item) && $item[0] === Type::T_LIST) {
+			// remove trailing null from the list
+			if ($removeTrailingNull && end($item[2]) === static::$null) {
+				array_pop($item[2]);
+			}
+
+			return $item;
+		}
+
+		if (isset($item) && $item[0] === Type::T_MAP) {
+			$keys = $item[1];
+			$values = $item[2];
+			$list = [];
+
+			for ($i = 0, $s = \count($keys); $i < $s; $i++) {
+				$key = $keys[$i];
+				$value = $values[$i];
+
+				switch ($key[0]) {
+					case Type::T_LIST:
+					case Type::T_MAP:
+					case Type::T_STRING:
+					case Type::T_NULL:
+						break;
+
+					default:
+						$key = [Type::T_KEYWORD, $this->compileStringContent($this->coerceString($key))];
+						break;
+				}
+
+				$list[] = [
+					Type::T_LIST,
+					'',
+					[$key, $value]
+				];
+			}
+
+			return [Type::T_LIST, ',', $list];
+		}
+
+		return [Type::T_LIST, $delim, ! isset($item) ? [] : [$item]];
+	}
+
+	/**
+	 * Coerce color for expression
+	 *
+	 * @param array $value
+	 *
+	 * @return array|null
+	 */
+	protected function coerceForExpression($value)
+	{
+		if ($color = $this->coerceColor($value)) {
+			return $color;
+		}
+
+		return $value;
+	}
+
+	/**
+	 * Coerce value to color
+	 *
+	 * @param array $value
+	 *
+	 * @return array|null
+	 */
+	protected function coerceColor($value, $inRGBFunction = false)
+	{
+		switch ($value[0]) {
+			case Type::T_COLOR:
+				for ($i = 1; $i <= 3; $i++) {
+					if (! is_numeric($value[$i])) {
+						$cv = $this->compileRGBAValue($value[$i]);
+
+						if (! is_numeric($cv)) {
+							return null;
+						}
+
+						$value[$i] = $cv;
+					}
+
+					if (isset($value[4])) {
+						if (! is_numeric($value[4])) {
+							$cv = $this->compileRGBAValue($value[4], true);
+
+							if (! is_numeric($cv)) {
+								return null;
+							}
+
+							$value[4] = $cv;
+						}
+					}
+				}
+
+				return $value;
+
+			case Type::T_LIST:
+				if ($inRGBFunction) {
+					if (\count($value[2]) == 3 || \count($value[2]) == 4) {
+						$color = $value[2];
+						array_unshift($color, Type::T_COLOR);
+
+						return $this->coerceColor($color);
+					}
+				}
+
+				return null;
+
+			case Type::T_KEYWORD:
+				if (! \is_string($value[1])) {
+					return null;
+				}
+
+				$name = strtolower($value[1]);
+
+				// hexa color?
+				if (preg_match('/^#([0-9a-f]+)$/i', $name, $m)) {
+					$nofValues = \strlen($m[1]);
+
+					if (\in_array($nofValues, [3, 4, 6, 8])) {
+						$nbChannels = 3;
+						$color      = [];
+						$num        = hexdec($m[1]);
+
+						switch ($nofValues) {
+							case 4:
+								$nbChannels = 4;
+								// then continuing with the case 3:
+							case 3:
+								for ($i = 0; $i < $nbChannels; $i++) {
+									$t = $num & 0xf;
+									array_unshift($color, $t << 4 | $t);
+									$num >>= 4;
+								}
+
+								break;
+
+							case 8:
+								$nbChannels = 4;
+								// then continuing with the case 6:
+							case 6:
+								for ($i = 0; $i < $nbChannels; $i++) {
+									array_unshift($color, $num & 0xff);
+									$num >>= 8;
+								}
+
+								break;
+						}
+
+						if ($nbChannels === 4) {
+							if ($color[3] === 255) {
+								$color[3] = 1; // fully opaque
+							} else {
+								$color[3] = round($color[3] / 255, Node\Number::PRECISION);
+							}
+						}
+
+						array_unshift($color, Type::T_COLOR);
+
+						return $color;
+					}
+				}
+
+				if ($rgba = Colors::colorNameToRGBa($name)) {
+					return isset($rgba[3])
+						? [Type::T_COLOR, $rgba[0], $rgba[1], $rgba[2], $rgba[3]]
+						: [Type::T_COLOR, $rgba[0], $rgba[1], $rgba[2]];
+				}
+
+				return null;
+		}
+
+		return null;
+	}
+
+	/**
+	 * @param integer|\ScssPhp\ScssPhp\Node\Number $value
+	 * @param boolean                              $isAlpha
+	 *
+	 * @return integer|mixed
+	 */
+	protected function compileRGBAValue($value, $isAlpha = false)
+	{
+		if ($isAlpha) {
+			return $this->compileColorPartValue($value, 0, 1, false);
+		}
+
+		return $this->compileColorPartValue($value, 0, 255, true);
+	}
+
+	/**
+	 * @param mixed         $value
+	 * @param integer|float $min
+	 * @param integer|float $max
+	 * @param boolean       $isInt
+	 * @param boolean       $clamp
+	 * @param boolean       $modulo
+	 *
+	 * @return integer|mixed
+	 */
+	protected function compileColorPartValue($value, $min, $max, $isInt = true, $clamp = true, $modulo = false)
+	{
+		if (! is_numeric($value)) {
+			if (\is_array($value)) {
+				$reduced = $this->reduce($value);
+
+				if (\is_object($reduced) && $value->type === Type::T_NUMBER) {
+					$value = $reduced;
+				}
+			}
+
+			if (\is_object($value) && $value->type === Type::T_NUMBER) {
+				$num = $value->dimension;
+
+				if (\count($value->units)) {
+					$unit = array_keys($value->units);
+					$unit = reset($unit);
+
+					switch ($unit) {
+						case '%':
+							$num *= $max / 100;
+							break;
+						default:
+							break;
+					}
+				}
+
+				$value = $num;
+			} elseif (\is_array($value)) {
+				$value = $this->compileValue($value);
+			}
+		}
+
+		if (is_numeric($value)) {
+			if ($isInt) {
+				$value = round($value);
+			}
+
+			if ($clamp) {
+				$value = min($max, max($min, $value));
+			}
+
+			if ($modulo) {
+				$value = $value % $max;
+
+				// still negative?
+				while ($value < $min) {
+					$value += $max;
+				}
+			}
+
+			return $value;
+		}
+
+		return $value;
+	}
+
+	/**
+	 * Coerce value to string
+	 *
+	 * @param array $value
+	 *
+	 * @return array|null
+	 */
+	protected function coerceString($value)
+	{
+		if ($value[0] === Type::T_STRING) {
+			return $value;
+		}
+
+		return [Type::T_STRING, '', [$this->compileValue($value)]];
+	}
+
+	/**
+	 * Coerce value to a percentage
+	 *
+	 * @param array $value
+	 *
+	 * @return integer|float
+	 */
+	protected function coercePercent($value)
+	{
+		if ($value[0] === Type::T_NUMBER) {
+			if (! empty($value[2]['%'])) {
+				return $value[1] / 100;
+			}
+
+			return $value[1];
+		}
+
+		return 0;
+	}
+
+	/**
+	 * Assert value is a map
+	 *
+	 * @api
+	 *
+	 * @param array $value
+	 *
+	 * @return array
+	 *
+	 * @throws \Exception
+	 */
+	public function assertMap($value)
+	{
+		$value = $this->coerceMap($value);
+
+		if ($value[0] !== Type::T_MAP) {
+			throw $this->error('expecting map, %s received', $value[0]);
+		}
+
+		return $value;
+	}
+
+	/**
+	 * Assert value is a list
+	 *
+	 * @api
+	 *
+	 * @param array $value
+	 *
+	 * @return array
+	 *
+	 * @throws \Exception
+	 */
+	public function assertList($value)
+	{
+		if ($value[0] !== Type::T_LIST) {
+			throw $this->error('expecting list, %s received', $value[0]);
+		}
+
+		return $value;
+	}
+
+	/**
+	 * Assert value is a color
+	 *
+	 * @api
+	 *
+	 * @param array $value
+	 *
+	 * @return array
+	 *
+	 * @throws \Exception
+	 */
+	public function assertColor($value)
+	{
+		if ($color = $this->coerceColor($value)) {
+			return $color;
+		}
+
+		throw $this->error('expecting color, %s received', $value[0]);
+	}
+
+	/**
+	 * Assert value is a number
+	 *
+	 * @api
+	 *
+	 * @param array $value
+	 *
+	 * @return integer|float
+	 *
+	 * @throws \Exception
+	 */
+	public function assertNumber($value)
+	{
+		if ($value[0] !== Type::T_NUMBER) {
+			throw $this->error('expecting number, %s received', $value[0]);
+		}
+
+		return $value[1];
+	}
+
+	/**
+	 * Make sure a color's components don't go out of bounds
+	 *
+	 * @param array $c
+	 *
+	 * @return array
+	 */
+	protected function fixColor($c)
+	{
+		foreach ([1, 2, 3] as $i) {
+			if ($c[$i] < 0) {
+				$c[$i] = 0;
+			}
+
+			if ($c[$i] > 255) {
+				$c[$i] = 255;
+			}
+		}
+
+		return $c;
+	}
+
+	/**
+	 * Convert RGB to HSL
+	 *
+	 * @api
+	 *
+	 * @param integer $red
+	 * @param integer $green
+	 * @param integer $blue
+	 *
+	 * @return array
+	 */
+	public function toHSL($red, $green, $blue)
+	{
+		$min = min($red, $green, $blue);
+		$max = max($red, $green, $blue);
+
+		$l = $min + $max;
+		$d = $max - $min;
+
+		if ((int) $d === 0) {
+			$h = $s = 0;
+		} else {
+			if ($l < 255) {
+				$s = $d / $l;
+			} else {
+				$s = $d / (510 - $l);
+			}
+
+			if ($red == $max) {
+				$h = 60 * ($green - $blue) / $d;
+			} elseif ($green == $max) {
+				$h = 60 * ($blue - $red) / $d + 120;
+			} elseif ($blue == $max) {
+				$h = 60 * ($red - $green) / $d + 240;
+			}
+		}
+
+		return [Type::T_HSL, fmod($h, 360), $s * 100, $l / 5.1];
+	}
+
+	/**
+	 * Hue to RGB helper
+	 *
+	 * @param float $m1
+	 * @param float $m2
+	 * @param float $h
+	 *
+	 * @return float
+	 */
+	protected function hueToRGB($m1, $m2, $h)
+	{
+		if ($h < 0) {
+			$h += 1;
+		} elseif ($h > 1) {
+			$h -= 1;
+		}
+
+		if ($h * 6 < 1) {
+			return $m1 + ($m2 - $m1) * $h * 6;
+		}
+
+		if ($h * 2 < 1) {
+			return $m2;
+		}
+
+		if ($h * 3 < 2) {
+			return $m1 + ($m2 - $m1) * (2 / 3 - $h) * 6;
+		}
+
+		return $m1;
+	}
+
+	/**
+	 * Convert HSL to RGB
+	 *
+	 * @api
+	 *
+	 * @param integer $hue        H from 0 to 360
+	 * @param integer $saturation S from 0 to 100
+	 * @param integer $lightness  L from 0 to 100
+	 *
+	 * @return array
+	 */
+	public function toRGB($hue, $saturation, $lightness)
+	{
+		if ($hue < 0) {
+			$hue += 360;
+		}
+
+		$h = $hue / 360;
+		$s = min(100, max(0, $saturation)) / 100;
+		$l = min(100, max(0, $lightness)) / 100;
+
+		$m2 = $l <= 0.5 ? $l * ($s + 1) : $l + $s - $l * $s;
+		$m1 = $l * 2 - $m2;
+
+		$r = $this->hueToRGB($m1, $m2, $h + 1 / 3) * 255;
+		$g = $this->hueToRGB($m1, $m2, $h) * 255;
+		$b = $this->hueToRGB($m1, $m2, $h - 1 / 3) * 255;
+
+		$out = [Type::T_COLOR, $r, $g, $b];
+
+		return $out;
+	}
+
+	// Built in functions
+
+	protected static $libCall = ['name', 'args...'];
+	protected function libCall($args, $kwargs)
+	{
+		$functionReference = $this->reduce(array_shift($args), true);
+
+		if (in_array($functionReference[0], [Type::T_STRING, Type::T_KEYWORD])) {
+			$name = $this->compileStringContent($this->coerceString($this->reduce($functionReference, true)));
+			$warning = "DEPRECATION WARNING: Passing a string to call() is deprecated and will be illegal\n"
+				. "in Sass 4.0. Use call(function-reference($name)) instead.";
+			fwrite($this->stderr, "$warning\n\n");
+			$functionReference = $this->libGetFunction([$functionReference]);
+		}
+
+		if ($functionReference === static::$null) {
+			return static::$null;
+		}
+
+		if (! in_array($functionReference[0], [Type::T_FUNCTION_REFERENCE, Type::T_FUNCTION])) {
+			throw $this->error('Function reference expected, got ' . $functionReference[0]);
+		}
+
+		$callArgs = [];
+
+		// $kwargs['args'] is [Type::T_LIST, ',', [..]]
+		foreach ($kwargs['args'][2] as $varname => $arg) {
+			if (is_numeric($varname)) {
+				$varname = null;
+			} else {
+				$varname = [ 'var', $varname];
+			}
+
+			$callArgs[] = [$varname, $arg, false];
+		}
+
+		return $this->reduce([Type::T_FUNCTION_CALL, $functionReference, $callArgs]);
+	}
+
+
+	protected static $libGetFunction = [
+		['name'],
+		['name', 'css']
+	];
+	protected function libGetFunction($args)
+	{
+		$name = $this->compileStringContent($this->coerceString($this->reduce(array_shift($args), true)));
+		$isCss = false;
+
+		if (count($args)) {
+			$isCss = $this->reduce(array_shift($args), true);
+			$isCss = (($isCss === static::$true) ? true : false);
+		}
+
+		if ($isCss) {
+			return [Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]];
+		}
+
+		return $this->getFunctionReference($name, true);
+	}
+
+	protected static $libIf = ['condition', 'if-true', 'if-false:'];
+	protected function libIf($args)
+	{
+		list($cond, $t, $f) = $args;
+
+		if (! $this->isTruthy($this->reduce($cond, true))) {
+			return $this->reduce($f, true);
+		}
+
+		return $this->reduce($t, true);
+	}
+
+	protected static $libIndex = ['list', 'value'];
+	protected function libIndex($args)
+	{
+		list($list, $value) = $args;
+
+		if (
+			$list[0] === Type::T_MAP ||
+			$list[0] === Type::T_STRING ||
+			$list[0] === Type::T_KEYWORD ||
+			$list[0] === Type::T_INTERPOLATE
+		) {
+			$list = $this->coerceList($list, ' ');
+		}
+
+		if ($list[0] !== Type::T_LIST) {
+			return static::$null;
+		}
+
+		$values = [];
+
+		foreach ($list[2] as $item) {
+			$values[] = $this->normalizeValue($item);
+		}
+
+		$key = array_search($this->normalizeValue($value), $values);
+
+		return false === $key ? static::$null : $key + 1;
+	}
+
+	protected static $libRgb = [
+		['color'],
+		['color', 'alpha'],
+		['channels'],
+		['red', 'green', 'blue'],
+		['red', 'green', 'blue', 'alpha'] ];
+	protected function libRgb($args, $kwargs, $funcName = 'rgb')
+	{
+		switch (\count($args)) {
+			case 1:
+				if (! $color = $this->coerceColor($args[0], true)) {
+					$color = [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
+				}
+				break;
+
+			case 3:
+				$color = [Type::T_COLOR, $args[0], $args[1], $args[2]];
+
+				if (! $color = $this->coerceColor($color)) {
+					$color = [Type::T_STRING, '', [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ')']];
+				}
+
+				return $color;
+
+			case 2:
+				if ($color = $this->coerceColor($args[0], true)) {
+					$alpha = $this->compileRGBAValue($args[1], true);
+
+					if (is_numeric($alpha)) {
+						$color[4] = $alpha;
+					} else {
+						$color = [Type::T_STRING, '',
+							[$funcName . '(', $color[1], ', ', $color[2], ', ', $color[3], ', ', $alpha, ')']];
+					}
+				} else {
+					$color = [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
+				}
+				break;
+
+			case 4:
+			default:
+				$color = [Type::T_COLOR, $args[0], $args[1], $args[2], $args[3]];
+
+				if (! $color = $this->coerceColor($color)) {
+					$color = [Type::T_STRING, '',
+						[$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ', ', $args[3], ')']];
+				}
+				break;
+		}
+
+		return $color;
+	}
+
+	protected static $libRgba = [
+		['color'],
+		['color', 'alpha'],
+		['channels'],
+		['red', 'green', 'blue'],
+		['red', 'green', 'blue', 'alpha'] ];
+	protected function libRgba($args, $kwargs)
+	{
+		return $this->libRgb($args, $kwargs, 'rgba');
+	}
+
+	// helper function for adjust_color, change_color, and scale_color
+	protected function alterColor($args, $fn)
+	{
+		$color = $this->assertColor($args[0]);
+
+		foreach ([1 => 1, 2 => 2, 3 => 3, 7 => 4] as $iarg => $irgba) {
+			if (isset($args[$iarg])) {
+				$val = $this->assertNumber($args[$iarg]);
+
+				if (! isset($color[$irgba])) {
+					$color[$irgba] = (($irgba < 4) ? 0 : 1);
+				}
+
+				$color[$irgba] = \call_user_func($fn, $color[$irgba], $val, $iarg);
+			}
+		}
+
+		if (! empty($args[4]) || ! empty($args[5]) || ! empty($args[6])) {
+			$hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+			foreach ([4 => 1, 5 => 2, 6 => 3] as $iarg => $ihsl) {
+				if (! empty($args[$iarg])) {
+					$val = $this->assertNumber($args[$iarg]);
+					$hsl[$ihsl] = \call_user_func($fn, $hsl[$ihsl], $val, $iarg);
+				}
+			}
+
+			$rgb = $this->toRGB($hsl[1], $hsl[2], $hsl[3]);
+
+			if (isset($color[4])) {
+				$rgb[4] = $color[4];
+			}
+
+			$color = $rgb;
+		}
+
+		return $color;
+	}
+
+	protected static $libAdjustColor = [
+		'color', 'red:null', 'green:null', 'blue:null',
+		'hue:null', 'saturation:null', 'lightness:null', 'alpha:null'
+	];
+	protected function libAdjustColor($args)
+	{
+		return $this->alterColor($args, function ($base, $alter, $i) {
+			return $base + $alter;
+		});
+	}
+
+	protected static $libChangeColor = [
+		'color', 'red:null', 'green:null', 'blue:null',
+		'hue:null', 'saturation:null', 'lightness:null', 'alpha:null'
+	];
+	protected function libChangeColor($args)
+	{
+		return $this->alterColor($args, function ($base, $alter, $i) {
+			return $alter;
+		});
+	}
+
+	protected static $libScaleColor = [
+		'color', 'red:null', 'green:null', 'blue:null',
+		'hue:null', 'saturation:null', 'lightness:null', 'alpha:null'
+	];
+	protected function libScaleColor($args)
+	{
+		return $this->alterColor($args, function ($base, $scale, $i) {
+			// 1, 2, 3 - rgb
+			// 4, 5, 6 - hsl
+			// 7 - a
+			switch ($i) {
+				case 1:
+				case 2:
+				case 3:
+					$max = 255;
+					break;
+
+				case 4:
+					$max = 360;
+					break;
+
+				case 7:
+					$max = 1;
+					break;
+
+				default:
+					$max = 100;
+			}
+
+			$scale = $scale / 100;
+
+			if ($scale < 0) {
+				return $base * $scale + $base;
+			}
+
+			return ($max - $base) * $scale + $base;
+		});
+	}
+
+	protected static $libIeHexStr = ['color'];
+	protected function libIeHexStr($args)
+	{
+		$color = $this->coerceColor($args[0]);
+
+		if (\is_null($color)) {
+			$this->throwError('Error: argument `$color` of `ie-hex-str($color)` must be a color');
+		}
+
+		$color[4] = isset($color[4]) ? round(255 * $color[4]) : 255;
+
+		return [Type::T_STRING, '', [sprintf('#%02X%02X%02X%02X', $color[4], $color[1], $color[2], $color[3])]];
+	}
+
+	protected static $libRed = ['color'];
+	protected function libRed($args)
+	{
+		$color = $this->coerceColor($args[0]);
+
+		if (\is_null($color)) {
+			$this->throwError('Error: argument `$color` of `red($color)` must be a color');
+		}
+
+		return $color[1];
+	}
+
+	protected static $libGreen = ['color'];
+	protected function libGreen($args)
+	{
+		$color = $this->coerceColor($args[0]);
+
+		if (\is_null($color)) {
+			$this->throwError('Error: argument `$color` of `green($color)` must be a color');
+		}
+
+		return $color[2];
+	}
+
+	protected static $libBlue = ['color'];
+	protected function libBlue($args)
+	{
+		$color = $this->coerceColor($args[0]);
+
+		if (\is_null($color)) {
+			$this->throwError('Error: argument `$color` of `blue($color)` must be a color');
+		}
+
+		return $color[3];
+	}
+
+	protected static $libAlpha = ['color'];
+	protected function libAlpha($args)
+	{
+		if ($color = $this->coerceColor($args[0])) {
+			return isset($color[4]) ? $color[4] : 1;
+		}
+
+		// this might be the IE function, so return value unchanged
+		return null;
+	}
+
+	protected static $libOpacity = ['color'];
+	protected function libOpacity($args)
+	{
+		$value = $args[0];
+
+		if ($value[0] === Type::T_NUMBER) {
+			return null;
+		}
+
+		return $this->libAlpha($args);
+	}
+
+	// mix two colors
+	protected static $libMix = [
+		['color1', 'color2', 'weight:0.5'],
+		['color-1', 'color-2', 'weight:0.5']
+		];
+	protected function libMix($args)
+	{
+		list($first, $second, $weight) = $args;
+
+		$first = $this->assertColor($first);
+		$second = $this->assertColor($second);
+
+		if (! isset($weight)) {
+			$weight = 0.5;
+		} else {
+			$weight = $this->coercePercent($weight);
+		}
+
+		$firstAlpha = isset($first[4]) ? $first[4] : 1;
+		$secondAlpha = isset($second[4]) ? $second[4] : 1;
+
+		$w = $weight * 2 - 1;
+		$a = $firstAlpha - $secondAlpha;
+
+		$w1 = (($w * $a === -1 ? $w : ($w + $a) / (1 + $w * $a)) + 1) / 2.0;
+		$w2 = 1.0 - $w1;
+
+		$new = [Type::T_COLOR,
+			$w1 * $first[1] + $w2 * $second[1],
+			$w1 * $first[2] + $w2 * $second[2],
+			$w1 * $first[3] + $w2 * $second[3],
+		];
+
+		if ($firstAlpha != 1.0 || $secondAlpha != 1.0) {
+			$new[] = $firstAlpha * $weight + $secondAlpha * (1 - $weight);
+		}
+
+		return $this->fixColor($new);
+	}
+
+	protected static $libHsl = [
+		['channels'],
+		['hue', 'saturation', 'lightness'],
+		['hue', 'saturation', 'lightness', 'alpha'] ];
+	protected function libHsl($args, $kwargs, $funcName = 'hsl')
+	{
+		$args_to_check = $args;
+
+		if (\count($args) == 1) {
+			if ($args[0][0] !== Type::T_LIST || \count($args[0][2]) < 3 || \count($args[0][2]) > 4) {
+				return [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
+			}
+
+			$args = $args[0][2];
+			$args_to_check = $kwargs['channels'][2];
+		}
+
+		$hue = $this->compileColorPartValue($args[0], 0, 360, false, false, true);
+		$saturation = $this->compileColorPartValue($args[1], 0, 100, false);
+		$lightness = $this->compileColorPartValue($args[2], 0, 100, false);
+
+		foreach ($kwargs as $k => $arg) {
+			if (in_array($arg[0], [Type::T_FUNCTION_CALL]) && in_array($arg[1], ['min', 'max'])) {
+				return null;
+			}
+		}
+
+		foreach ($args_to_check as $k => $arg) {
+			if (in_array($arg[0], [Type::T_FUNCTION_CALL]) && in_array($arg[1], ['min', 'max'])) {
+				if (count($kwargs) > 1 || ($k >= 2 && count($args) === 4)) {
+					return null;
+				}
+
+				$args[$k] = $this->stringifyFncallArgs($arg);
+				$hue = '';
+			}
+
+			if (
+				$k >= 2 && count($args) === 4 &&
+				in_array($arg[0], [Type::T_FUNCTION_CALL, Type::T_FUNCTION]) &&
+				in_array($arg[1], ['calc','env'])
+			) {
+				return null;
+			}
+		}
+
+		$alpha = null;
+
+		if (\count($args) === 4) {
+			$alpha = $this->compileColorPartValue($args[3], 0, 100, false);
+
+			if (! is_numeric($hue) || ! is_numeric($saturation) || ! is_numeric($lightness) || ! is_numeric($alpha)) {
+				return [Type::T_STRING, '',
+					[$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ', ', $args[3], ')']];
+			}
+		} else {
+			if (! is_numeric($hue) || ! is_numeric($saturation) || ! is_numeric($lightness)) {
+				return [Type::T_STRING, '', [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ')']];
+			}
+		}
+
+		$color = $this->toRGB($hue, $saturation, $lightness);
+
+		if (! \is_null($alpha)) {
+			$color[4] = $alpha;
+		}
+
+		return $color;
+	}
+
+	protected static $libHsla = [
+			['channels'],
+			['hue', 'saturation', 'lightness'],
+			['hue', 'saturation', 'lightness', 'alpha']];
+	protected function libHsla($args, $kwargs)
+	{
+		return $this->libHsl($args, $kwargs, 'hsla');
+	}
+
+	protected static $libHue = ['color'];
+	protected function libHue($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+		return new Node\Number($hsl[1], 'deg');
+	}
+
+	protected static $libSaturation = ['color'];
+	protected function libSaturation($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+		return new Node\Number($hsl[2], '%');
+	}
+
+	protected static $libLightness = ['color'];
+	protected function libLightness($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+		return new Node\Number($hsl[3], '%');
+	}
+
+	protected function adjustHsl($color, $idx, $amount)
+	{
+		$hsl = $this->toHSL($color[1], $color[2], $color[3]);
+		$hsl[$idx] += $amount;
+		$out = $this->toRGB($hsl[1], $hsl[2], $hsl[3]);
+
+		if (isset($color[4])) {
+			$out[4] = $color[4];
+		}
+
+		return $out;
+	}
+
+	protected static $libAdjustHue = ['color', 'degrees'];
+	protected function libAdjustHue($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$degrees = $this->assertNumber($args[1]);
+
+		return $this->adjustHsl($color, 1, $degrees);
+	}
+
+	protected static $libLighten = ['color', 'amount'];
+	protected function libLighten($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$amount = Util::checkRange('amount', new Range(0, 100), $args[1], '%');
+
+		return $this->adjustHsl($color, 3, $amount);
+	}
+
+	protected static $libDarken = ['color', 'amount'];
+	protected function libDarken($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$amount = Util::checkRange('amount', new Range(0, 100), $args[1], '%');
+
+		return $this->adjustHsl($color, 3, -$amount);
+	}
+
+	protected static $libSaturate = [['color', 'amount'], ['amount']];
+	protected function libSaturate($args)
+	{
+		$value = $args[0];
+
+		if ($value[0] === Type::T_NUMBER) {
+			return null;
+		}
+
+		if (count($args) === 1) {
+			$val = $this->compileValue($value);
+			throw $this->error("\$amount: $val is not a number");
+		}
+
+		$color = $this->assertColor($value);
+		$amount = 100 * $this->coercePercent($args[1]);
+
+		return $this->adjustHsl($color, 2, $amount);
+	}
+
+	protected static $libDesaturate = ['color', 'amount'];
+	protected function libDesaturate($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$amount = 100 * $this->coercePercent($args[1]);
+
+		return $this->adjustHsl($color, 2, -$amount);
+	}
+
+	protected static $libGrayscale = ['color'];
+	protected function libGrayscale($args)
+	{
+		$value = $args[0];
+
+		if ($value[0] === Type::T_NUMBER) {
+			return null;
+		}
+
+		return $this->adjustHsl($this->assertColor($value), 2, -100);
+	}
+
+	protected static $libComplement = ['color'];
+	protected function libComplement($args)
+	{
+		return $this->adjustHsl($this->assertColor($args[0]), 1, 180);
+	}
+
+	protected static $libInvert = ['color', 'weight:1'];
+	protected function libInvert($args)
+	{
+		list($value, $weight) = $args;
+
+		if (! isset($weight)) {
+			$weight = 1;
+		} else {
+			$weight = $this->coercePercent($weight);
+		}
+
+		if ($value[0] === Type::T_NUMBER) {
+			return null;
+		}
+
+		$color = $this->assertColor($value);
+		$inverted = $color;
+		$inverted[1] = 255 - $inverted[1];
+		$inverted[2] = 255 - $inverted[2];
+		$inverted[3] = 255 - $inverted[3];
+
+		if ($weight < 1) {
+			return $this->libMix([$inverted, $color, [Type::T_NUMBER, $weight]]);
+		}
+
+		return $inverted;
+	}
+
+	// increases opacity by amount
+	protected static $libOpacify = ['color', 'amount'];
+	protected function libOpacify($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$amount = $this->coercePercent($args[1]);
+
+		$color[4] = (isset($color[4]) ? $color[4] : 1) + $amount;
+		$color[4] = min(1, max(0, $color[4]));
+
+		return $color;
+	}
+
+	protected static $libFadeIn = ['color', 'amount'];
+	protected function libFadeIn($args)
+	{
+		return $this->libOpacify($args);
+	}
+
+	// decreases opacity by amount
+	protected static $libTransparentize = ['color', 'amount'];
+	protected function libTransparentize($args)
+	{
+		$color = $this->assertColor($args[0]);
+		$amount = $this->coercePercent($args[1]);
+
+		$color[4] = (isset($color[4]) ? $color[4] : 1) - $amount;
+		$color[4] = min(1, max(0, $color[4]));
+
+		return $color;
+	}
+
+	protected static $libFadeOut = ['color', 'amount'];
+	protected function libFadeOut($args)
+	{
+		return $this->libTransparentize($args);
+	}
+
+	protected static $libUnquote = ['string'];
+	protected function libUnquote($args)
+	{
+		$str = $args[0];
+
+		if ($str[0] === Type::T_STRING) {
+			$str[1] = '';
+		}
+
+		return $str;
+	}
+
+	protected static $libQuote = ['string'];
+	protected function libQuote($args)
+	{
+		$value = $args[0];
+
+		if ($value[0] === Type::T_STRING && ! empty($value[1])) {
+			return $value;
+		}
+
+		return [Type::T_STRING, '"', [$value]];
+	}
+
+	protected static $libPercentage = ['number'];
+	protected function libPercentage($args)
+	{
+		return new Node\Number($this->coercePercent($args[0]) * 100, '%');
+	}
+
+	protected static $libRound = ['number'];
+	protected function libRound($args)
+	{
+		$num = $args[0];
+
+		return new Node\Number(round($num[1]), $num[2]);
+	}
+
+	protected static $libFloor = ['number'];
+	protected function libFloor($args)
+	{
+		$num = $args[0];
+
+		return new Node\Number(floor($num[1]), $num[2]);
+	}
+
+	protected static $libCeil = ['number'];
+	protected function libCeil($args)
+	{
+		$num = $args[0];
+
+		return new Node\Number(ceil($num[1]), $num[2]);
+	}
+
+	protected static $libAbs = ['number'];
+	protected function libAbs($args)
+	{
+		$num = $args[0];
+
+		return new Node\Number(abs($num[1]), $num[2]);
+	}
+
+	protected function libMin($args)
+	{
+		$numbers = $this->getNormalizedNumbers($args);
+		$minOriginal = null;
+		$minNormalized = null;
+
+		foreach ($numbers as $key => $pair) {
+			list($original, $normalized) = $pair;
+
+			if (\is_null($normalized) || \is_null($minNormalized)) {
+				if (\is_null($minOriginal) || $original[1] <= $minOriginal[1]) {
+					$minOriginal = $original;
+					$minNormalized = $normalized;
+				}
+			} elseif ($normalized[1] <= $minNormalized[1]) {
+				$minOriginal = $original;
+				$minNormalized = $normalized;
+			}
+		}
+
+		return $minOriginal;
+	}
+
+	protected function libMax($args)
+	{
+		$numbers = $this->getNormalizedNumbers($args);
+		$maxOriginal = null;
+		$maxNormalized = null;
+
+		foreach ($numbers as $key => $pair) {
+			list($original, $normalized) = $pair;
+
+			if (\is_null($normalized) || \is_null($maxNormalized)) {
+				if (\is_null($maxOriginal) || $original[1] >= $maxOriginal[1]) {
+					$maxOriginal = $original;
+					$maxNormalized = $normalized;
+				}
+			} elseif ($normalized[1] >= $maxNormalized[1]) {
+				$maxOriginal = $original;
+				$maxNormalized = $normalized;
+			}
+		}
+
+		return $maxOriginal;
+	}
+
+	/**
+	 * Helper to normalize args containing numbers
+	 *
+	 * @param array $args
+	 *
+	 * @return array
+	 */
+	protected function getNormalizedNumbers($args)
+	{
+		$unit         = null;
+		$originalUnit = null;
+		$numbers      = [];
+
+		foreach ($args as $key => $item) {
+			if ($item[0] !== Type::T_NUMBER) {
+				throw $this->error('%s is not a number', $item[0]);
+			}
+
+			$number = $item->normalize();
+
+			if (empty($unit)) {
+				$unit = $number[2];
+				$originalUnit = $item->unitStr();
+			} elseif ($number[1] && $unit !== $number[2] && ! empty($number[2])) {
+				throw $this->error('Incompatible units: "%s" and "%s".', $originalUnit, $item->unitStr());
+			}
+
+			$numbers[$key] = [$args[$key], empty($number[2]) ? null : $number];
+		}
+
+		return $numbers;
+	}
+
+	protected static $libLength = ['list'];
+	protected function libLength($args)
+	{
+		$list = $this->coerceList($args[0], ',', true);
+
+		return \count($list[2]);
+	}
+
+	//protected static $libListSeparator = ['list...'];
+	protected function libListSeparator($args)
+	{
+		if (\count($args) > 1) {
+			return 'comma';
+		}
+
+		$list = $this->coerceList($args[0]);
+
+		if (\count($list[2]) <= 1) {
+			return 'space';
+		}
+
+		if ($list[1] === ',') {
+			return 'comma';
+		}
+
+		return 'space';
+	}
+
+	protected static $libNth = ['list', 'n'];
+	protected function libNth($args)
+	{
+		$list = $this->coerceList($args[0], ',', false);
+		$n = $this->assertNumber($args[1]);
+
+		if ($n > 0) {
+			$n--;
+		} elseif ($n < 0) {
+			$n += \count($list[2]);
+		}
+
+		return isset($list[2][$n]) ? $list[2][$n] : static::$defaultValue;
+	}
+
+	protected static $libSetNth = ['list', 'n', 'value'];
+	protected function libSetNth($args)
+	{
+		$list = $this->coerceList($args[0]);
+		$n = $this->assertNumber($args[1]);
+
+		if ($n > 0) {
+			$n--;
+		} elseif ($n < 0) {
+			$n += \count($list[2]);
+		}
+
+		if (! isset($list[2][$n])) {
+			throw $this->error('Invalid argument for "n"');
+		}
+
+		$list[2][$n] = $args[2];
+
+		return $list;
+	}
+
+	protected static $libMapGet = ['map', 'key'];
+	protected function libMapGet($args)
+	{
+		$map = $this->assertMap($args[0]);
+		$key = $args[1];
+
+		if (! \is_null($key)) {
+			$key = $this->compileStringContent($this->coerceString($key));
+
+			for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
+				if ($key === $this->compileStringContent($this->coerceString($map[1][$i]))) {
+					return $map[2][$i];
+				}
+			}
+		}
+
+		return static::$null;
+	}
+
+	protected static $libMapKeys = ['map'];
+	protected function libMapKeys($args)
+	{
+		$map = $this->assertMap($args[0]);
+		$keys = $map[1];
+
+		return [Type::T_LIST, ',', $keys];
+	}
+
+	protected static $libMapValues = ['map'];
+	protected function libMapValues($args)
+	{
+		$map = $this->assertMap($args[0]);
+		$values = $map[2];
+
+		return [Type::T_LIST, ',', $values];
+	}
+
+	protected static $libMapRemove = ['map', 'key...'];
+	protected function libMapRemove($args)
+	{
+		$map = $this->assertMap($args[0]);
+		$keyList = $this->assertList($args[1]);
+
+		$keys = [];
+
+		foreach ($keyList[2] as $key) {
+			$keys[] = $this->compileStringContent($this->coerceString($key));
+		}
+
+		for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
+			if (in_array($this->compileStringContent($this->coerceString($map[1][$i])), $keys)) {
+				array_splice($map[1], $i, 1);
+				array_splice($map[2], $i, 1);
+			}
+		}
+
+		return $map;
+	}
+
+	protected static $libMapHasKey = ['map', 'key'];
+	protected function libMapHasKey($args)
+	{
+		$map = $this->assertMap($args[0]);
+		$key = $this->compileStringContent($this->coerceString($args[1]));
+
+		for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
+			if ($key === $this->compileStringContent($this->coerceString($map[1][$i]))) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	protected static $libMapMerge = [
+		['map1', 'map2'],
+		['map-1', 'map-2']
+	];
+	protected function libMapMerge($args)
+	{
+		$map1 = $this->assertMap($args[0]);
+		$map2 = $this->assertMap($args[1]);
+
+		foreach ($map2[1] as $i2 => $key2) {
+			$key = $this->compileStringContent($this->coerceString($key2));
+
+			foreach ($map1[1] as $i1 => $key1) {
+				if ($key === $this->compileStringContent($this->coerceString($key1))) {
+					$map1[2][$i1] = $map2[2][$i2];
+					continue 2;
+				}
+			}
+
+			$map1[1][] = $map2[1][$i2];
+			$map1[2][] = $map2[2][$i2];
+		}
+
+		return $map1;
+	}
+
+	protected static $libKeywords = ['args'];
+	protected function libKeywords($args)
+	{
+		$this->assertList($args[0]);
+
+		$keys = [];
+		$values = [];
+
+		foreach ($args[0][2] as $name => $arg) {
+			$keys[] = [Type::T_KEYWORD, $name];
+			$values[] = $arg;
+		}
+
+		return [Type::T_MAP, $keys, $values];
+	}
+
+	protected static $libIsBracketed = ['list'];
+	protected function libIsBracketed($args)
+	{
+		$list = $args[0];
+		$this->coerceList($list, ' ');
+
+		if (! empty($list['enclosing']) && $list['enclosing'] === 'bracket') {
+			return true;
+		}
+
+		return false;
+	}
+
+	protected function listSeparatorForJoin($list1, $sep)
+	{
+		if (! isset($sep)) {
+			return $list1[1];
+		}
+
+		switch ($this->compileValue($sep)) {
+			case 'comma':
+				return ',';
+
+			case 'space':
+				return ' ';
+
+			default:
+				return $list1[1];
+		}
+	}
+
+	protected static $libJoin = ['list1', 'list2', 'separator:null', 'bracketed:auto'];
+	protected function libJoin($args)
+	{
+		list($list1, $list2, $sep, $bracketed) = $args;
+
+		$list1 = $this->coerceList($list1, ' ', true);
+		$list2 = $this->coerceList($list2, ' ', true);
+		$sep   = $this->listSeparatorForJoin($list1, $sep);
+
+		if ($bracketed === static::$true) {
+			$bracketed = true;
+		} elseif ($bracketed === static::$false) {
+			$bracketed = false;
+		} elseif ($bracketed === [Type::T_KEYWORD, 'auto']) {
+			$bracketed = 'auto';
+		} elseif ($bracketed === static::$null) {
+			$bracketed = false;
+		} else {
+			$bracketed = $this->compileValue($bracketed);
+			$bracketed = ! ! $bracketed;
+
+			if ($bracketed === true) {
+				$bracketed = true;
+			}
+		}
+
+		if ($bracketed === 'auto') {
+			$bracketed = false;
+
+			if (! empty($list1['enclosing']) && $list1['enclosing'] === 'bracket') {
+				$bracketed = true;
+			}
+		}
+
+		$res = [Type::T_LIST, $sep, array_merge($list1[2], $list2[2])];
+
+		if (isset($list1['enclosing'])) {
+			$res['enlcosing'] = $list1['enclosing'];
+		}
+
+		if ($bracketed) {
+			$res['enclosing'] = 'bracket';
+		}
+
+		return $res;
+	}
+
+	protected static $libAppend = ['list', 'val', 'separator:null'];
+	protected function libAppend($args)
+	{
+		list($list1, $value, $sep) = $args;
+
+		$list1 = $this->coerceList($list1, ' ', true);
+		$sep   = $this->listSeparatorForJoin($list1, $sep);
+		$res   = [Type::T_LIST, $sep, array_merge($list1[2], [$value])];
+
+		if (isset($list1['enclosing'])) {
+			$res['enclosing'] = $list1['enclosing'];
+		}
+
+		return $res;
+	}
+
+	protected function libZip($args)
+	{
+		foreach ($args as $key => $arg) {
+			$args[$key] = $this->coerceList($arg);
+		}
+
+		$lists = [];
+		$firstList = array_shift($args);
+
+		foreach ($firstList[2] as $key => $item) {
+			$list = [Type::T_LIST, '', [$item]];
+
+			foreach ($args as $arg) {
+				if (isset($arg[2][$key])) {
+					$list[2][] = $arg[2][$key];
+				} else {
+					break 2;
+				}
+			}
+
+			$lists[] = $list;
+		}
+
+		return [Type::T_LIST, ',', $lists];
+	}
+
+	protected static $libTypeOf = ['value'];
+	protected function libTypeOf($args)
+	{
+		$value = $args[0];
+
+		switch ($value[0]) {
+			case Type::T_KEYWORD:
+				if ($value === static::$true || $value === static::$false) {
+					return 'bool';
+				}
+
+				if ($this->coerceColor($value)) {
+					return 'color';
+				}
+
+				// fall-thru
+			case Type::T_FUNCTION:
+				return 'string';
+
+			case Type::T_FUNCTION_REFERENCE:
+				return 'function';
+
+			case Type::T_LIST:
+				if (isset($value[3]) && $value[3]) {
+					return 'arglist';
+				}
+
+				// fall-thru
+			default:
+				return $value[0];
+		}
+	}
+
+	protected static $libUnit = ['number'];
+	protected function libUnit($args)
+	{
+		$num = $args[0];
+
+		if ($num[0] === Type::T_NUMBER) {
+			return [Type::T_STRING, '"', [$num->unitStr()]];
+		}
+
+		return '';
+	}
 
-    protected static $libUnitless = ['number'];
-    protected function libUnitless($args)
-    {
-        $value = $args[0];
+	protected static $libUnitless = ['number'];
+	protected function libUnitless($args)
+	{
+		$value = $args[0];
 
-        return $value[0] === Type::T_NUMBER && $value->unitless();
-    }
-
-    protected static $libComparable = [
-        ['number1', 'number2'],
-        ['number-1', 'number-2']
-    ];
-    protected function libComparable($args)
-    {
-        list($number1, $number2) = $args;
+		return $value[0] === Type::T_NUMBER && $value->unitless();
+	}
+
+	protected static $libComparable = [
+		['number1', 'number2'],
+		['number-1', 'number-2']
+	];
+	protected function libComparable($args)
+	{
+		list($number1, $number2) = $args;
 
-        if (
-            ! isset($number1[0]) || $number1[0] !== Type::T_NUMBER ||
-            ! isset($number2[0]) || $number2[0] !== Type::T_NUMBER
-        ) {
-            throw $this->error('Invalid argument(s) for "comparable"');
-        }
-
-        $number1 = $number1->normalize();
-        $number2 = $number2->normalize();
-
-        return $number1[2] === $number2[2] || $number1->unitless() || $number2->unitless();
-    }
-
-    protected static $libStrIndex = ['string', 'substring'];
-    protected function libStrIndex($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $stringContent = $this->compileStringContent($string);
-
-        $substring = $this->coerceString($args[1]);
-        $substringContent = $this->compileStringContent($substring);
-
-        $result = strpos($stringContent, $substringContent);
-
-        return $result === false ? static::$null : new Node\Number($result + 1, '');
-    }
-
-    protected static $libStrInsert = ['string', 'insert', 'index'];
-    protected function libStrInsert($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $stringContent = $this->compileStringContent($string);
+		if (
+			! isset($number1[0]) || $number1[0] !== Type::T_NUMBER ||
+			! isset($number2[0]) || $number2[0] !== Type::T_NUMBER
+		) {
+			throw $this->error('Invalid argument(s) for "comparable"');
+		}
+
+		$number1 = $number1->normalize();
+		$number2 = $number2->normalize();
+
+		return $number1[2] === $number2[2] || $number1->unitless() || $number2->unitless();
+	}
+
+	protected static $libStrIndex = ['string', 'substring'];
+	protected function libStrIndex($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$stringContent = $this->compileStringContent($string);
+
+		$substring = $this->coerceString($args[1]);
+		$substringContent = $this->compileStringContent($substring);
+
+		$result = strpos($stringContent, $substringContent);
+
+		return $result === false ? static::$null : new Node\Number($result + 1, '');
+	}
+
+	protected static $libStrInsert = ['string', 'insert', 'index'];
+	protected function libStrInsert($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$stringContent = $this->compileStringContent($string);
 
-        $insert = $this->coerceString($args[1]);
-        $insertContent = $this->compileStringContent($insert);
+		$insert = $this->coerceString($args[1]);
+		$insertContent = $this->compileStringContent($insert);
 
-        list(, $index) = $args[2];
-
-        $string[2] = [substr_replace($stringContent, $insertContent, $index - 1, 0)];
-
-        return $string;
-    }
+		list(, $index) = $args[2];
+
+		$string[2] = [substr_replace($stringContent, $insertContent, $index - 1, 0)];
+
+		return $string;
+	}
 
-    protected static $libStrLength = ['string'];
-    protected function libStrLength($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $stringContent = $this->compileStringContent($string);
+	protected static $libStrLength = ['string'];
+	protected function libStrLength($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$stringContent = $this->compileStringContent($string);
 
-        return new Node\Number(\strlen($stringContent), '');
-    }
+		return new Node\Number(\strlen($stringContent), '');
+	}
 
-    protected static $libStrSlice = ['string', 'start-at', 'end-at:-1'];
-    protected function libStrSlice($args)
-    {
-        if (isset($args[2]) && ! $args[2][1]) {
-            return static::$nullString;
-        }
-
-        $string = $this->coerceString($args[0]);
-        $stringContent = $this->compileStringContent($string);
-
-        $start = (int) $args[1][1];
-
-        if ($start > 0) {
-            $start--;
-        }
-
-        $end    = isset($args[2]) ? (int) $args[2][1] : -1;
-        $length = $end < 0 ? $end + 1 : ($end > 0 ? $end - $start : $end);
-
-        $string[2] = $length
-            ? [substr($stringContent, $start, $length)]
-            : [substr($stringContent, $start)];
-
-        return $string;
-    }
-
-    protected static $libToLowerCase = ['string'];
-    protected function libToLowerCase($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $stringContent = $this->compileStringContent($string);
-
-        $string[2] = [\function_exists('mb_strtolower') ? mb_strtolower($stringContent) : strtolower($stringContent)];
-
-        return $string;
-    }
-
-    protected static $libToUpperCase = ['string'];
-    protected function libToUpperCase($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $stringContent = $this->compileStringContent($string);
-
-        $string[2] = [\function_exists('mb_strtoupper') ? mb_strtoupper($stringContent) : strtoupper($stringContent)];
-
-        return $string;
-    }
+	protected static $libStrSlice = ['string', 'start-at', 'end-at:-1'];
+	protected function libStrSlice($args)
+	{
+		if (isset($args[2]) && ! $args[2][1]) {
+			return static::$nullString;
+		}
+
+		$string = $this->coerceString($args[0]);
+		$stringContent = $this->compileStringContent($string);
+
+		$start = (int) $args[1][1];
+
+		if ($start > 0) {
+			$start--;
+		}
+
+		$end    = isset($args[2]) ? (int) $args[2][1] : -1;
+		$length = $end < 0 ? $end + 1 : ($end > 0 ? $end - $start : $end);
+
+		$string[2] = $length
+			? [substr($stringContent, $start, $length)]
+			: [substr($stringContent, $start)];
+
+		return $string;
+	}
+
+	protected static $libToLowerCase = ['string'];
+	protected function libToLowerCase($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$stringContent = $this->compileStringContent($string);
+
+		$string[2] = [\function_exists('mb_strtolower') ? mb_strtolower($stringContent) : strtolower($stringContent)];
+
+		return $string;
+	}
+
+	protected static $libToUpperCase = ['string'];
+	protected function libToUpperCase($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$stringContent = $this->compileStringContent($string);
+
+		$string[2] = [\function_exists('mb_strtoupper') ? mb_strtoupper($stringContent) : strtoupper($stringContent)];
+
+		return $string;
+	}
 
-    protected static $libFeatureExists = ['feature'];
-    protected function libFeatureExists($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $name = $this->compileStringContent($string);
+	protected static $libFeatureExists = ['feature'];
+	protected function libFeatureExists($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$name = $this->compileStringContent($string);
 
-        return $this->toBool(
-            \array_key_exists($name, $this->registeredFeatures) ? $this->registeredFeatures[$name] : false
-        );
-    }
+		return $this->toBool(
+			\array_key_exists($name, $this->registeredFeatures) ? $this->registeredFeatures[$name] : false
+		);
+	}
 
-    protected static $libFunctionExists = ['name'];
-    protected function libFunctionExists($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $name = $this->compileStringContent($string);
+	protected static $libFunctionExists = ['name'];
+	protected function libFunctionExists($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$name = $this->compileStringContent($string);
 
-        // user defined functions
-        if ($this->has(static::$namespaces['function'] . $name)) {
-            return true;
-        }
+		// user defined functions
+		if ($this->has(static::$namespaces['function'] . $name)) {
+			return true;
+		}
 
-        $name = $this->normalizeName($name);
-
-        if (isset($this->userFunctions[$name])) {
-            return true;
-        }
-
-        // built-in functions
-        $f = $this->getBuiltinFunction($name);
-
-        return $this->toBool(\is_callable($f));
-    }
-
-    protected static $libGlobalVariableExists = ['name'];
-    protected function libGlobalVariableExists($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $name = $this->compileStringContent($string);
-
-        return $this->has($name, $this->rootEnv);
-    }
-
-    protected static $libMixinExists = ['name'];
-    protected function libMixinExists($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $name = $this->compileStringContent($string);
-
-        return $this->has(static::$namespaces['mixin'] . $name);
-    }
-
-    protected static $libVariableExists = ['name'];
-    protected function libVariableExists($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $name = $this->compileStringContent($string);
-
-        return $this->has($name);
-    }
-
-    /**
-     * Workaround IE7's content counter bug.
-     *
-     * @param array $args
-     *
-     * @return array
-     */
-    protected function libCounter($args)
-    {
-        $list = array_map([$this, 'compileValue'], $args);
-
-        return [Type::T_STRING, '', ['counter(' . implode(',', $list) . ')']];
-    }
-
-    protected static $libRandom = ['limit:1'];
-    protected function libRandom($args)
-    {
-        if (isset($args[0])) {
-            $n = $this->assertNumber($args[0]);
-
-            if ($n < 1) {
-                throw $this->error("\$limit must be greater than or equal to 1");
-            }
-
-            if ($n - \intval($n) > 0) {
-                throw $this->error("Expected \$limit to be an integer but got $n for `random`");
-            }
-
-            return new Node\Number(mt_rand(1, \intval($n)), '');
-        }
-
-        return new Node\Number(mt_rand(1, mt_getrandmax()), '');
-    }
-
-    protected function libUniqueId()
-    {
-        static $id;
-
-        if (! isset($id)) {
-            $id = PHP_INT_SIZE === 4
-                ? mt_rand(0, pow(36, 5)) . str_pad(mt_rand(0, pow(36, 5)) % 10000000, 7, '0', STR_PAD_LEFT)
-                : mt_rand(0, pow(36, 8));
-        }
-
-        $id += mt_rand(0, 10) + 1;
-
-        return [Type::T_STRING, '', ['u' . str_pad(base_convert($id, 10, 36), 8, '0', STR_PAD_LEFT)]];
-    }
-
-    protected function inspectFormatValue($value, $force_enclosing_display = false)
-    {
-        if ($value === static::$null) {
-            $value = [Type::T_KEYWORD, 'null'];
-        }
-
-        $stringValue = [$value];
-
-        if ($value[0] === Type::T_LIST) {
-            if (end($value[2]) === static::$null) {
-                array_pop($value[2]);
-                $value[2][] = [Type::T_STRING, '', ['']];
-                $force_enclosing_display = true;
-            }
-
-            if (
-                ! empty($value['enclosing']) &&
-                ($force_enclosing_display ||
-                    ($value['enclosing'] === 'bracket') ||
-                    ! \count($value[2]))
-            ) {
-                $value['enclosing'] = 'forced_' . $value['enclosing'];
-                $force_enclosing_display = true;
-            }
-
-            foreach ($value[2] as $k => $listelement) {
-                $value[2][$k] = $this->inspectFormatValue($listelement, $force_enclosing_display);
-            }
-
-            $stringValue = [$value];
-        }
-
-        return [Type::T_STRING, '', $stringValue];
-    }
-
-    protected static $libInspect = ['value'];
-    protected function libInspect($args)
-    {
-        $value = $args[0];
-
-        return $this->inspectFormatValue($value);
-    }
-
-    /**
-     * Preprocess selector args
-     *
-     * @param array $arg
-     *
-     * @return array|boolean
-     */
-    protected function getSelectorArg($arg)
-    {
-        static $parser = null;
-
-        if (\is_null($parser)) {
-            $parser = $this->parserFactory(__METHOD__);
-        }
-
-        $arg = $this->libUnquote([$arg]);
-        $arg = $this->compileValue($arg);
-
-        $parsedSelector = [];
-
-        if ($parser->parseSelector($arg, $parsedSelector)) {
-            $selector = $this->evalSelectors($parsedSelector);
-            $gluedSelector = $this->glueFunctionSelectors($selector);
-
-            return $gluedSelector;
-        }
-
-        return false;
-    }
-
-    /**
-     * Postprocess selector to output in right format
-     *
-     * @param array $selectors
-     *
-     * @return string
-     */
-    protected function formatOutputSelector($selectors)
-    {
-        $selectors = $this->collapseSelectors($selectors, true);
-
-        return $selectors;
-    }
-
-    protected static $libIsSuperselector = ['super', 'sub'];
-    protected function libIsSuperselector($args)
-    {
-        list($super, $sub) = $args;
-
-        $super = $this->getSelectorArg($super);
-        $sub = $this->getSelectorArg($sub);
-
-        return $this->isSuperSelector($super, $sub);
-    }
-
-    /**
-     * Test a $super selector again $sub
-     *
-     * @param array $super
-     * @param array $sub
-     *
-     * @return boolean
-     */
-    protected function isSuperSelector($super, $sub)
-    {
-        // one and only one selector for each arg
-        if (! $super || \count($super) !== 1) {
-            throw $this->error('Invalid super selector for isSuperSelector()');
-        }
-
-        if (! $sub || \count($sub) !== 1) {
-            throw $this->error('Invalid sub selector for isSuperSelector()');
-        }
-
-        $super = reset($super);
-        $sub = reset($sub);
-
-        $i = 0;
-        $nextMustMatch = false;
-
-        foreach ($super as $node) {
-            $compound = '';
-
-            array_walk_recursive(
-                $node,
-                function ($value, $key) use (&$compound) {
-                    $compound .= $value;
-                }
-            );
-
-            if ($this->isImmediateRelationshipCombinator($compound)) {
-                if ($node !== $sub[$i]) {
-                    return false;
-                }
-
-                $nextMustMatch = true;
-                $i++;
-            } else {
-                while ($i < \count($sub) && ! $this->isSuperPart($node, $sub[$i])) {
-                    if ($nextMustMatch) {
-                        return false;
-                    }
-
-                    $i++;
-                }
-
-                if ($i >= \count($sub)) {
-                    return false;
-                }
-
-                $nextMustMatch = false;
-                $i++;
-            }
-        }
-
-        return true;
-    }
-
-    /**
-     * Test a part of super selector again a part of sub selector
-     *
-     * @param array $superParts
-     * @param array $subParts
-     *
-     * @return boolean
-     */
-    protected function isSuperPart($superParts, $subParts)
-    {
-        $i = 0;
-
-        foreach ($superParts as $superPart) {
-            while ($i < \count($subParts) && $subParts[$i] !== $superPart) {
-                $i++;
-            }
-
-            if ($i >= \count($subParts)) {
-                return false;
-            }
-
-            $i++;
-        }
-
-        return true;
-    }
-
-    protected static $libSelectorAppend = ['selector...'];
-    protected function libSelectorAppend($args)
-    {
-        // get the selector... list
-        $args = reset($args);
-        $args = $args[2];
-
-        if (\count($args) < 1) {
-            throw $this->error('selector-append() needs at least 1 argument');
-        }
-
-        $selectors = array_map([$this, 'getSelectorArg'], $args);
-
-        return $this->formatOutputSelector($this->selectorAppend($selectors));
-    }
-
-    /**
-     * Append parts of the last selector in the list to the previous, recursively
-     *
-     * @param array $selectors
-     *
-     * @return array
-     *
-     * @throws \ScssPhp\ScssPhp\Exception\CompilerException
-     */
-    protected function selectorAppend($selectors)
-    {
-        $lastSelectors = array_pop($selectors);
-
-        if (! $lastSelectors) {
-            throw $this->error('Invalid selector list in selector-append()');
-        }
-
-        while (\count($selectors)) {
-            $previousSelectors = array_pop($selectors);
-
-            if (! $previousSelectors) {
-                throw $this->error('Invalid selector list in selector-append()');
-            }
-
-            // do the trick, happening $lastSelector to $previousSelector
-            $appended = [];
-
-            foreach ($lastSelectors as $lastSelector) {
-                $previous = $previousSelectors;
-
-                foreach ($lastSelector as $lastSelectorParts) {
-                    foreach ($lastSelectorParts as $lastSelectorPart) {
-                        foreach ($previous as $i => $previousSelector) {
-                            foreach ($previousSelector as $j => $previousSelectorParts) {
-                                $previous[$i][$j][] = $lastSelectorPart;
-                            }
-                        }
-                    }
-                }
-
-                foreach ($previous as $ps) {
-                    $appended[] = $ps;
-                }
-            }
-
-            $lastSelectors = $appended;
-        }
-
-        return $lastSelectors;
-    }
-
-    protected static $libSelectorExtend = [
-        ['selector', 'extendee', 'extender'],
-        ['selectors', 'extendee', 'extender']
-    ];
-    protected function libSelectorExtend($args)
-    {
-        list($selectors, $extendee, $extender) = $args;
-
-        $selectors = $this->getSelectorArg($selectors);
-        $extendee  = $this->getSelectorArg($extendee);
-        $extender  = $this->getSelectorArg($extender);
-
-        if (! $selectors || ! $extendee || ! $extender) {
-            throw $this->error('selector-extend() invalid arguments');
-        }
-
-        $extended = $this->extendOrReplaceSelectors($selectors, $extendee, $extender);
-
-        return $this->formatOutputSelector($extended);
-    }
-
-    protected static $libSelectorReplace = [
-        ['selector', 'original', 'replacement'],
-        ['selectors', 'original', 'replacement']
-    ];
-    protected function libSelectorReplace($args)
-    {
-        list($selectors, $original, $replacement) = $args;
-
-        $selectors   = $this->getSelectorArg($selectors);
-        $original    = $this->getSelectorArg($original);
-        $replacement = $this->getSelectorArg($replacement);
-
-        if (! $selectors || ! $original || ! $replacement) {
-            throw $this->error('selector-replace() invalid arguments');
-        }
-
-        $replaced = $this->extendOrReplaceSelectors($selectors, $original, $replacement, true);
-
-        return $this->formatOutputSelector($replaced);
-    }
-
-    /**
-     * Extend/replace in selectors
-     * used by selector-extend and selector-replace that use the same logic
-     *
-     * @param array   $selectors
-     * @param array   $extendee
-     * @param array   $extender
-     * @param boolean $replace
-     *
-     * @return array
-     */
-    protected function extendOrReplaceSelectors($selectors, $extendee, $extender, $replace = false)
-    {
-        $saveExtends = $this->extends;
-        $saveExtendsMap = $this->extendsMap;
-
-        $this->extends = [];
-        $this->extendsMap = [];
-
-        foreach ($extendee as $es) {
-            // only use the first one
-            $this->pushExtends(reset($es), $extender, null);
-        }
-
-        $extended = [];
-
-        foreach ($selectors as $selector) {
-            if (! $replace) {
-                $extended[] = $selector;
-            }
-
-            $n = \count($extended);
-
-            $this->matchExtends($selector, $extended);
-
-            // if didnt match, keep the original selector if we are in a replace operation
-            if ($replace && \count($extended) === $n) {
-                $extended[] = $selector;
-            }
-        }
-
-        $this->extends = $saveExtends;
-        $this->extendsMap = $saveExtendsMap;
-
-        return $extended;
-    }
-
-    protected static $libSelectorNest = ['selector...'];
-    protected function libSelectorNest($args)
-    {
-        // get the selector... list
-        $args = reset($args);
-        $args = $args[2];
-
-        if (\count($args) < 1) {
-            throw $this->error('selector-nest() needs at least 1 argument');
-        }
-
-        $selectorsMap = array_map([$this, 'getSelectorArg'], $args);
-        $envs = [];
-
-        foreach ($selectorsMap as $selectors) {
-            $env = new Environment();
-            $env->selectors = $selectors;
-
-            $envs[] = $env;
-        }
-
-        $envs            = array_reverse($envs);
-        $env             = $this->extractEnv($envs);
-        $outputSelectors = $this->multiplySelectors($env);
-
-        return $this->formatOutputSelector($outputSelectors);
-    }
-
-    protected static $libSelectorParse = [
-        ['selector'],
-        ['selectors']
-    ];
-    protected function libSelectorParse($args)
-    {
-        $selectors = reset($args);
-        $selectors = $this->getSelectorArg($selectors);
-
-        return $this->formatOutputSelector($selectors);
-    }
-
-    protected static $libSelectorUnify = ['selectors1', 'selectors2'];
-    protected function libSelectorUnify($args)
-    {
-        list($selectors1, $selectors2) = $args;
-
-        $selectors1 = $this->getSelectorArg($selectors1);
-        $selectors2 = $this->getSelectorArg($selectors2);
-
-        if (! $selectors1 || ! $selectors2) {
-            throw $this->error('selector-unify() invalid arguments');
-        }
-
-        // only consider the first compound of each
-        $compound1 = reset($selectors1);
-        $compound2 = reset($selectors2);
-
-        // unify them and that's it
-        $unified = $this->unifyCompoundSelectors($compound1, $compound2);
-
-        return $this->formatOutputSelector($unified);
-    }
-
-    /**
-     * The selector-unify magic as its best
-     * (at least works as expected on test cases)
-     *
-     * @param array $compound1
-     * @param array $compound2
-     *
-     * @return array|mixed
-     */
-    protected function unifyCompoundSelectors($compound1, $compound2)
-    {
-        if (! \count($compound1)) {
-            return $compound2;
-        }
+		$name = $this->normalizeName($name);
+
+		if (isset($this->userFunctions[$name])) {
+			return true;
+		}
+
+		// built-in functions
+		$f = $this->getBuiltinFunction($name);
+
+		return $this->toBool(\is_callable($f));
+	}
+
+	protected static $libGlobalVariableExists = ['name'];
+	protected function libGlobalVariableExists($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$name = $this->compileStringContent($string);
+
+		return $this->has($name, $this->rootEnv);
+	}
+
+	protected static $libMixinExists = ['name'];
+	protected function libMixinExists($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$name = $this->compileStringContent($string);
+
+		return $this->has(static::$namespaces['mixin'] . $name);
+	}
+
+	protected static $libVariableExists = ['name'];
+	protected function libVariableExists($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$name = $this->compileStringContent($string);
+
+		return $this->has($name);
+	}
+
+	/**
+	 * Workaround IE7's content counter bug.
+	 *
+	 * @param array $args
+	 *
+	 * @return array
+	 */
+	protected function libCounter($args)
+	{
+		$list = array_map([$this, 'compileValue'], $args);
+
+		return [Type::T_STRING, '', ['counter(' . implode(',', $list) . ')']];
+	}
+
+	protected static $libRandom = ['limit:1'];
+	protected function libRandom($args)
+	{
+		if (isset($args[0])) {
+			$n = $this->assertNumber($args[0]);
+
+			if ($n < 1) {
+				throw $this->error("\$limit must be greater than or equal to 1");
+			}
+
+			if ($n - \intval($n) > 0) {
+				throw $this->error("Expected \$limit to be an integer but got $n for `random`");
+			}
+
+			return new Node\Number(mt_rand(1, \intval($n)), '');
+		}
+
+		return new Node\Number(mt_rand(1, mt_getrandmax()), '');
+	}
+
+	protected function libUniqueId()
+	{
+		static $id;
+
+		if (! isset($id)) {
+			$id = PHP_INT_SIZE === 4
+				? mt_rand(0, pow(36, 5)) . str_pad(mt_rand(0, pow(36, 5)) % 10000000, 7, '0', STR_PAD_LEFT)
+				: mt_rand(0, pow(36, 8));
+		}
+
+		$id += mt_rand(0, 10) + 1;
+
+		return [Type::T_STRING, '', ['u' . str_pad(base_convert($id, 10, 36), 8, '0', STR_PAD_LEFT)]];
+	}
+
+	protected function inspectFormatValue($value, $force_enclosing_display = false)
+	{
+		if ($value === static::$null) {
+			$value = [Type::T_KEYWORD, 'null'];
+		}
+
+		$stringValue = [$value];
+
+		if ($value[0] === Type::T_LIST) {
+			if (end($value[2]) === static::$null) {
+				array_pop($value[2]);
+				$value[2][] = [Type::T_STRING, '', ['']];
+				$force_enclosing_display = true;
+			}
+
+			if (
+				! empty($value['enclosing']) &&
+				($force_enclosing_display ||
+					($value['enclosing'] === 'bracket') ||
+					! \count($value[2]))
+			) {
+				$value['enclosing'] = 'forced_' . $value['enclosing'];
+				$force_enclosing_display = true;
+			}
+
+			foreach ($value[2] as $k => $listelement) {
+				$value[2][$k] = $this->inspectFormatValue($listelement, $force_enclosing_display);
+			}
+
+			$stringValue = [$value];
+		}
+
+		return [Type::T_STRING, '', $stringValue];
+	}
+
+	protected static $libInspect = ['value'];
+	protected function libInspect($args)
+	{
+		$value = $args[0];
+
+		return $this->inspectFormatValue($value);
+	}
+
+	/**
+	 * Preprocess selector args
+	 *
+	 * @param array $arg
+	 *
+	 * @return array|boolean
+	 */
+	protected function getSelectorArg($arg)
+	{
+		static $parser = null;
+
+		if (\is_null($parser)) {
+			$parser = $this->parserFactory(__METHOD__);
+		}
+
+		$arg = $this->libUnquote([$arg]);
+		$arg = $this->compileValue($arg);
+
+		$parsedSelector = [];
+
+		if ($parser->parseSelector($arg, $parsedSelector)) {
+			$selector = $this->evalSelectors($parsedSelector);
+			$gluedSelector = $this->glueFunctionSelectors($selector);
+
+			return $gluedSelector;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Postprocess selector to output in right format
+	 *
+	 * @param array $selectors
+	 *
+	 * @return string
+	 */
+	protected function formatOutputSelector($selectors)
+	{
+		$selectors = $this->collapseSelectors($selectors, true);
+
+		return $selectors;
+	}
+
+	protected static $libIsSuperselector = ['super', 'sub'];
+	protected function libIsSuperselector($args)
+	{
+		list($super, $sub) = $args;
+
+		$super = $this->getSelectorArg($super);
+		$sub = $this->getSelectorArg($sub);
+
+		return $this->isSuperSelector($super, $sub);
+	}
+
+	/**
+	 * Test a $super selector again $sub
+	 *
+	 * @param array $super
+	 * @param array $sub
+	 *
+	 * @return boolean
+	 */
+	protected function isSuperSelector($super, $sub)
+	{
+		// one and only one selector for each arg
+		if (! $super || \count($super) !== 1) {
+			throw $this->error('Invalid super selector for isSuperSelector()');
+		}
+
+		if (! $sub || \count($sub) !== 1) {
+			throw $this->error('Invalid sub selector for isSuperSelector()');
+		}
+
+		$super = reset($super);
+		$sub = reset($sub);
+
+		$i = 0;
+		$nextMustMatch = false;
+
+		foreach ($super as $node) {
+			$compound = '';
+
+			array_walk_recursive(
+				$node,
+				function ($value, $key) use (&$compound) {
+					$compound .= $value;
+				}
+			);
+
+			if ($this->isImmediateRelationshipCombinator($compound)) {
+				if ($node !== $sub[$i]) {
+					return false;
+				}
+
+				$nextMustMatch = true;
+				$i++;
+			} else {
+				while ($i < \count($sub) && ! $this->isSuperPart($node, $sub[$i])) {
+					if ($nextMustMatch) {
+						return false;
+					}
+
+					$i++;
+				}
+
+				if ($i >= \count($sub)) {
+					return false;
+				}
+
+				$nextMustMatch = false;
+				$i++;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * Test a part of super selector again a part of sub selector
+	 *
+	 * @param array $superParts
+	 * @param array $subParts
+	 *
+	 * @return boolean
+	 */
+	protected function isSuperPart($superParts, $subParts)
+	{
+		$i = 0;
+
+		foreach ($superParts as $superPart) {
+			while ($i < \count($subParts) && $subParts[$i] !== $superPart) {
+				$i++;
+			}
+
+			if ($i >= \count($subParts)) {
+				return false;
+			}
+
+			$i++;
+		}
+
+		return true;
+	}
+
+	protected static $libSelectorAppend = ['selector...'];
+	protected function libSelectorAppend($args)
+	{
+		// get the selector... list
+		$args = reset($args);
+		$args = $args[2];
+
+		if (\count($args) < 1) {
+			throw $this->error('selector-append() needs at least 1 argument');
+		}
+
+		$selectors = array_map([$this, 'getSelectorArg'], $args);
+
+		return $this->formatOutputSelector($this->selectorAppend($selectors));
+	}
+
+	/**
+	 * Append parts of the last selector in the list to the previous, recursively
+	 *
+	 * @param array $selectors
+	 *
+	 * @return array
+	 *
+	 * @throws \ScssPhp\ScssPhp\Exception\CompilerException
+	 */
+	protected function selectorAppend($selectors)
+	{
+		$lastSelectors = array_pop($selectors);
+
+		if (! $lastSelectors) {
+			throw $this->error('Invalid selector list in selector-append()');
+		}
+
+		while (\count($selectors)) {
+			$previousSelectors = array_pop($selectors);
+
+			if (! $previousSelectors) {
+				throw $this->error('Invalid selector list in selector-append()');
+			}
+
+			// do the trick, happening $lastSelector to $previousSelector
+			$appended = [];
+
+			foreach ($lastSelectors as $lastSelector) {
+				$previous = $previousSelectors;
+
+				foreach ($lastSelector as $lastSelectorParts) {
+					foreach ($lastSelectorParts as $lastSelectorPart) {
+						foreach ($previous as $i => $previousSelector) {
+							foreach ($previousSelector as $j => $previousSelectorParts) {
+								$previous[$i][$j][] = $lastSelectorPart;
+							}
+						}
+					}
+				}
+
+				foreach ($previous as $ps) {
+					$appended[] = $ps;
+				}
+			}
+
+			$lastSelectors = $appended;
+		}
+
+		return $lastSelectors;
+	}
+
+	protected static $libSelectorExtend = [
+		['selector', 'extendee', 'extender'],
+		['selectors', 'extendee', 'extender']
+	];
+	protected function libSelectorExtend($args)
+	{
+		list($selectors, $extendee, $extender) = $args;
+
+		$selectors = $this->getSelectorArg($selectors);
+		$extendee  = $this->getSelectorArg($extendee);
+		$extender  = $this->getSelectorArg($extender);
+
+		if (! $selectors || ! $extendee || ! $extender) {
+			throw $this->error('selector-extend() invalid arguments');
+		}
+
+		$extended = $this->extendOrReplaceSelectors($selectors, $extendee, $extender);
+
+		return $this->formatOutputSelector($extended);
+	}
+
+	protected static $libSelectorReplace = [
+		['selector', 'original', 'replacement'],
+		['selectors', 'original', 'replacement']
+	];
+	protected function libSelectorReplace($args)
+	{
+		list($selectors, $original, $replacement) = $args;
+
+		$selectors   = $this->getSelectorArg($selectors);
+		$original    = $this->getSelectorArg($original);
+		$replacement = $this->getSelectorArg($replacement);
+
+		if (! $selectors || ! $original || ! $replacement) {
+			throw $this->error('selector-replace() invalid arguments');
+		}
+
+		$replaced = $this->extendOrReplaceSelectors($selectors, $original, $replacement, true);
+
+		return $this->formatOutputSelector($replaced);
+	}
+
+	/**
+	 * Extend/replace in selectors
+	 * used by selector-extend and selector-replace that use the same logic
+	 *
+	 * @param array   $selectors
+	 * @param array   $extendee
+	 * @param array   $extender
+	 * @param boolean $replace
+	 *
+	 * @return array
+	 */
+	protected function extendOrReplaceSelectors($selectors, $extendee, $extender, $replace = false)
+	{
+		$saveExtends = $this->extends;
+		$saveExtendsMap = $this->extendsMap;
+
+		$this->extends = [];
+		$this->extendsMap = [];
+
+		foreach ($extendee as $es) {
+			// only use the first one
+			$this->pushExtends(reset($es), $extender, null);
+		}
+
+		$extended = [];
+
+		foreach ($selectors as $selector) {
+			if (! $replace) {
+				$extended[] = $selector;
+			}
+
+			$n = \count($extended);
+
+			$this->matchExtends($selector, $extended);
+
+			// if didnt match, keep the original selector if we are in a replace operation
+			if ($replace && \count($extended) === $n) {
+				$extended[] = $selector;
+			}
+		}
+
+		$this->extends = $saveExtends;
+		$this->extendsMap = $saveExtendsMap;
+
+		return $extended;
+	}
+
+	protected static $libSelectorNest = ['selector...'];
+	protected function libSelectorNest($args)
+	{
+		// get the selector... list
+		$args = reset($args);
+		$args = $args[2];
+
+		if (\count($args) < 1) {
+			throw $this->error('selector-nest() needs at least 1 argument');
+		}
+
+		$selectorsMap = array_map([$this, 'getSelectorArg'], $args);
+		$envs = [];
+
+		foreach ($selectorsMap as $selectors) {
+			$env = new Environment();
+			$env->selectors = $selectors;
+
+			$envs[] = $env;
+		}
+
+		$envs            = array_reverse($envs);
+		$env             = $this->extractEnv($envs);
+		$outputSelectors = $this->multiplySelectors($env);
+
+		return $this->formatOutputSelector($outputSelectors);
+	}
+
+	protected static $libSelectorParse = [
+		['selector'],
+		['selectors']
+	];
+	protected function libSelectorParse($args)
+	{
+		$selectors = reset($args);
+		$selectors = $this->getSelectorArg($selectors);
+
+		return $this->formatOutputSelector($selectors);
+	}
+
+	protected static $libSelectorUnify = ['selectors1', 'selectors2'];
+	protected function libSelectorUnify($args)
+	{
+		list($selectors1, $selectors2) = $args;
+
+		$selectors1 = $this->getSelectorArg($selectors1);
+		$selectors2 = $this->getSelectorArg($selectors2);
+
+		if (! $selectors1 || ! $selectors2) {
+			throw $this->error('selector-unify() invalid arguments');
+		}
+
+		// only consider the first compound of each
+		$compound1 = reset($selectors1);
+		$compound2 = reset($selectors2);
+
+		// unify them and that's it
+		$unified = $this->unifyCompoundSelectors($compound1, $compound2);
+
+		return $this->formatOutputSelector($unified);
+	}
+
+	/**
+	 * The selector-unify magic as its best
+	 * (at least works as expected on test cases)
+	 *
+	 * @param array $compound1
+	 * @param array $compound2
+	 *
+	 * @return array|mixed
+	 */
+	protected function unifyCompoundSelectors($compound1, $compound2)
+	{
+		if (! \count($compound1)) {
+			return $compound2;
+		}
 
-        if (! \count($compound2)) {
-            return $compound1;
-        }
-
-        // check that last part are compatible
-        $lastPart1 = array_pop($compound1);
-        $lastPart2 = array_pop($compound2);
-        $last      = $this->mergeParts($lastPart1, $lastPart2);
-
-        if (! $last) {
-            return [[]];
-        }
-
-        $unifiedCompound = [$last];
-        $unifiedSelectors = [$unifiedCompound];
-
-        // do the rest
-        while (\count($compound1) || \count($compound2)) {
-            $part1 = end($compound1);
-            $part2 = end($compound2);
-
-            if ($part1 && ($match2 = $this->matchPartInCompound($part1, $compound2))) {
-                list($compound2, $part2, $after2) = $match2;
-
-                if ($after2) {
-                    $unifiedSelectors = $this->prependSelectors($unifiedSelectors, $after2);
-                }
-
-                $c = $this->mergeParts($part1, $part2);
-                $unifiedSelectors = $this->prependSelectors($unifiedSelectors, [$c]);
-
-                $part1 = $part2 = null;
-
-                array_pop($compound1);
-            }
-
-            if ($part2 && ($match1 = $this->matchPartInCompound($part2, $compound1))) {
-                list($compound1, $part1, $after1) = $match1;
-
-                if ($after1) {
-                    $unifiedSelectors = $this->prependSelectors($unifiedSelectors, $after1);
-                }
-
-                $c = $this->mergeParts($part2, $part1);
-                $unifiedSelectors = $this->prependSelectors($unifiedSelectors, [$c]);
-
-                $part1 = $part2 = null;
-
-                array_pop($compound2);
-            }
-
-            $new = [];
-
-            if ($part1 && $part2) {
-                array_pop($compound1);
-                array_pop($compound2);
-
-                $s   = $this->prependSelectors($unifiedSelectors, [$part2]);
-                $new = array_merge($new, $this->prependSelectors($s, [$part1]));
-                $s   = $this->prependSelectors($unifiedSelectors, [$part1]);
-                $new = array_merge($new, $this->prependSelectors($s, [$part2]));
-            } elseif ($part1) {
-                array_pop($compound1);
-
-                $new = array_merge($new, $this->prependSelectors($unifiedSelectors, [$part1]));
-            } elseif ($part2) {
-                array_pop($compound2);
-
-                $new = array_merge($new, $this->prependSelectors($unifiedSelectors, [$part2]));
-            }
-
-            if ($new) {
-                $unifiedSelectors = $new;
-            }
-        }
-
-        return $unifiedSelectors;
-    }
-
-    /**
-     * Prepend each selector from $selectors with $parts
-     *
-     * @param array $selectors
-     * @param array $parts
-     *
-     * @return array
-     */
-    protected function prependSelectors($selectors, $parts)
-    {
-        $new = [];
-
-        foreach ($selectors as $compoundSelector) {
-            array_unshift($compoundSelector, $parts);
-
-            $new[] = $compoundSelector;
-        }
-
-        return $new;
-    }
-
-    /**
-     * Try to find a matching part in a compound:
-     * - with same html tag name
-     * - with some class or id or something in common
-     *
-     * @param array $part
-     * @param array $compound
-     *
-     * @return array|boolean
-     */
-    protected function matchPartInCompound($part, $compound)
-    {
-        $partTag = $this->findTagName($part);
-        $before  = $compound;
-        $after   = [];
-
-        // try to find a match by tag name first
-        while (\count($before)) {
-            $p = array_pop($before);
-
-            if ($partTag && $partTag !== '*' && $partTag == $this->findTagName($p)) {
-                return [$before, $p, $after];
-            }
-
-            $after[] = $p;
-        }
-
-        // try again matching a non empty intersection and a compatible tagname
-        $before = $compound;
-        $after = [];
-
-        while (\count($before)) {
-            $p = array_pop($before);
-
-            if ($this->checkCompatibleTags($partTag, $this->findTagName($p))) {
-                if (\count(array_intersect($part, $p))) {
-                    return [$before, $p, $after];
-                }
-            }
-
-            $after[] = $p;
-        }
-
-        return false;
-    }
-
-    /**
-     * Merge two part list taking care that
-     * - the html tag is coming first - if any
-     * - the :something are coming last
-     *
-     * @param array $parts1
-     * @param array $parts2
-     *
-     * @return array
-     */
-    protected function mergeParts($parts1, $parts2)
-    {
-        $tag1 = $this->findTagName($parts1);
-        $tag2 = $this->findTagName($parts2);
-        $tag  = $this->checkCompatibleTags($tag1, $tag2);
-
-        // not compatible tags
-        if ($tag === false) {
-            return [];
-        }
-
-        if ($tag) {
-            if ($tag1) {
-                $parts1 = array_diff($parts1, [$tag1]);
-            }
-
-            if ($tag2) {
-                $parts2 = array_diff($parts2, [$tag2]);
-            }
-        }
-
-        $mergedParts = array_merge($parts1, $parts2);
-        $mergedOrderedParts = [];
-
-        foreach ($mergedParts as $part) {
-            if (strpos($part, ':') === 0) {
-                $mergedOrderedParts[] = $part;
-            }
-        }
-
-        $mergedParts = array_diff($mergedParts, $mergedOrderedParts);
-        $mergedParts = array_merge($mergedParts, $mergedOrderedParts);
-
-        if ($tag) {
-            array_unshift($mergedParts, $tag);
-        }
-
-        return $mergedParts;
-    }
-
-    /**
-     * Check the compatibility between two tag names:
-     * if both are defined they should be identical or one has to be '*'
-     *
-     * @param string $tag1
-     * @param string $tag2
-     *
-     * @return array|boolean
-     */
-    protected function checkCompatibleTags($tag1, $tag2)
-    {
-        $tags = [$tag1, $tag2];
-        $tags = array_unique($tags);
-        $tags = array_filter($tags);
-
-        if (\count($tags) > 1) {
-            $tags = array_diff($tags, ['*']);
-        }
-
-        // not compatible nodes
-        if (\count($tags) > 1) {
-            return false;
-        }
-
-        return $tags;
-    }
-
-    /**
-     * Find the html tag name in a selector parts list
-     *
-     * @param array $parts
-     *
-     * @return mixed|string
-     */
-    protected function findTagName($parts)
-    {
-        foreach ($parts as $part) {
-            if (! preg_match('/^[\[.:#%_-]/', $part)) {
-                return $part;
-            }
-        }
-
-        return '';
-    }
-
-    protected static $libSimpleSelectors = ['selector'];
-    protected function libSimpleSelectors($args)
-    {
-        $selector = reset($args);
-        $selector = $this->getSelectorArg($selector);
-
-        // remove selectors list layer, keeping the first one
-        $selector = reset($selector);
-
-        // remove parts list layer, keeping the first part
-        $part = reset($selector);
-
-        $listParts = [];
-
-        foreach ($part as $p) {
-            $listParts[] = [Type::T_STRING, '', [$p]];
-        }
-
-        return [Type::T_LIST, ',', $listParts];
-    }
-
-    protected static $libScssphpGlob = ['pattern'];
-    protected function libScssphpGlob($args)
-    {
-        $string = $this->coerceString($args[0]);
-        $pattern = $this->compileStringContent($string);
-        $matches = glob($pattern);
-        $listParts = [];
-
-        foreach ($matches as $match) {
-            if (! is_file($match)) {
-                continue;
-            }
-
-            $listParts[] = [Type::T_STRING, '"', [$match]];
-        }
-
-        return [Type::T_LIST, ',', $listParts];
-    }
+		if (! \count($compound2)) {
+			return $compound1;
+		}
+
+		// check that last part are compatible
+		$lastPart1 = array_pop($compound1);
+		$lastPart2 = array_pop($compound2);
+		$last      = $this->mergeParts($lastPart1, $lastPart2);
+
+		if (! $last) {
+			return [[]];
+		}
+
+		$unifiedCompound = [$last];
+		$unifiedSelectors = [$unifiedCompound];
+
+		// do the rest
+		while (\count($compound1) || \count($compound2)) {
+			$part1 = end($compound1);
+			$part2 = end($compound2);
+
+			if ($part1 && ($match2 = $this->matchPartInCompound($part1, $compound2))) {
+				list($compound2, $part2, $after2) = $match2;
+
+				if ($after2) {
+					$unifiedSelectors = $this->prependSelectors($unifiedSelectors, $after2);
+				}
+
+				$c = $this->mergeParts($part1, $part2);
+				$unifiedSelectors = $this->prependSelectors($unifiedSelectors, [$c]);
+
+				$part1 = $part2 = null;
+
+				array_pop($compound1);
+			}
+
+			if ($part2 && ($match1 = $this->matchPartInCompound($part2, $compound1))) {
+				list($compound1, $part1, $after1) = $match1;
+
+				if ($after1) {
+					$unifiedSelectors = $this->prependSelectors($unifiedSelectors, $after1);
+				}
+
+				$c = $this->mergeParts($part2, $part1);
+				$unifiedSelectors = $this->prependSelectors($unifiedSelectors, [$c]);
+
+				$part1 = $part2 = null;
+
+				array_pop($compound2);
+			}
+
+			$new = [];
+
+			if ($part1 && $part2) {
+				array_pop($compound1);
+				array_pop($compound2);
+
+				$s   = $this->prependSelectors($unifiedSelectors, [$part2]);
+				$new = array_merge($new, $this->prependSelectors($s, [$part1]));
+				$s   = $this->prependSelectors($unifiedSelectors, [$part1]);
+				$new = array_merge($new, $this->prependSelectors($s, [$part2]));
+			} elseif ($part1) {
+				array_pop($compound1);
+
+				$new = array_merge($new, $this->prependSelectors($unifiedSelectors, [$part1]));
+			} elseif ($part2) {
+				array_pop($compound2);
+
+				$new = array_merge($new, $this->prependSelectors($unifiedSelectors, [$part2]));
+			}
+
+			if ($new) {
+				$unifiedSelectors = $new;
+			}
+		}
+
+		return $unifiedSelectors;
+	}
+
+	/**
+	 * Prepend each selector from $selectors with $parts
+	 *
+	 * @param array $selectors
+	 * @param array $parts
+	 *
+	 * @return array
+	 */
+	protected function prependSelectors($selectors, $parts)
+	{
+		$new = [];
+
+		foreach ($selectors as $compoundSelector) {
+			array_unshift($compoundSelector, $parts);
+
+			$new[] = $compoundSelector;
+		}
+
+		return $new;
+	}
+
+	/**
+	 * Try to find a matching part in a compound:
+	 * - with same html tag name
+	 * - with some class or id or something in common
+	 *
+	 * @param array $part
+	 * @param array $compound
+	 *
+	 * @return array|boolean
+	 */
+	protected function matchPartInCompound($part, $compound)
+	{
+		$partTag = $this->findTagName($part);
+		$before  = $compound;
+		$after   = [];
+
+		// try to find a match by tag name first
+		while (\count($before)) {
+			$p = array_pop($before);
+
+			if ($partTag && $partTag !== '*' && $partTag == $this->findTagName($p)) {
+				return [$before, $p, $after];
+			}
+
+			$after[] = $p;
+		}
+
+		// try again matching a non empty intersection and a compatible tagname
+		$before = $compound;
+		$after = [];
+
+		while (\count($before)) {
+			$p = array_pop($before);
+
+			if ($this->checkCompatibleTags($partTag, $this->findTagName($p))) {
+				if (\count(array_intersect($part, $p))) {
+					return [$before, $p, $after];
+				}
+			}
+
+			$after[] = $p;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Merge two part list taking care that
+	 * - the html tag is coming first - if any
+	 * - the :something are coming last
+	 *
+	 * @param array $parts1
+	 * @param array $parts2
+	 *
+	 * @return array
+	 */
+	protected function mergeParts($parts1, $parts2)
+	{
+		$tag1 = $this->findTagName($parts1);
+		$tag2 = $this->findTagName($parts2);
+		$tag  = $this->checkCompatibleTags($tag1, $tag2);
+
+		// not compatible tags
+		if ($tag === false) {
+			return [];
+		}
+
+		if ($tag) {
+			if ($tag1) {
+				$parts1 = array_diff($parts1, [$tag1]);
+			}
+
+			if ($tag2) {
+				$parts2 = array_diff($parts2, [$tag2]);
+			}
+		}
+
+		$mergedParts = array_merge($parts1, $parts2);
+		$mergedOrderedParts = [];
+
+		foreach ($mergedParts as $part) {
+			if (strpos($part, ':') === 0) {
+				$mergedOrderedParts[] = $part;
+			}
+		}
+
+		$mergedParts = array_diff($mergedParts, $mergedOrderedParts);
+		$mergedParts = array_merge($mergedParts, $mergedOrderedParts);
+
+		if ($tag) {
+			array_unshift($mergedParts, $tag);
+		}
+
+		return $mergedParts;
+	}
+
+	/**
+	 * Check the compatibility between two tag names:
+	 * if both are defined they should be identical or one has to be '*'
+	 *
+	 * @param string $tag1
+	 * @param string $tag2
+	 *
+	 * @return array|boolean
+	 */
+	protected function checkCompatibleTags($tag1, $tag2)
+	{
+		$tags = [$tag1, $tag2];
+		$tags = array_unique($tags);
+		$tags = array_filter($tags);
+
+		if (\count($tags) > 1) {
+			$tags = array_diff($tags, ['*']);
+		}
+
+		// not compatible nodes
+		if (\count($tags) > 1) {
+			return false;
+		}
+
+		return $tags;
+	}
+
+	/**
+	 * Find the html tag name in a selector parts list
+	 *
+	 * @param array $parts
+	 *
+	 * @return mixed|string
+	 */
+	protected function findTagName($parts)
+	{
+		foreach ($parts as $part) {
+			if (! preg_match('/^[\[.:#%_-]/', $part)) {
+				return $part;
+			}
+		}
+
+		return '';
+	}
+
+	protected static $libSimpleSelectors = ['selector'];
+	protected function libSimpleSelectors($args)
+	{
+		$selector = reset($args);
+		$selector = $this->getSelectorArg($selector);
+
+		// remove selectors list layer, keeping the first one
+		$selector = reset($selector);
+
+		// remove parts list layer, keeping the first part
+		$part = reset($selector);
+
+		$listParts = [];
+
+		foreach ($part as $p) {
+			$listParts[] = [Type::T_STRING, '', [$p]];
+		}
+
+		return [Type::T_LIST, ',', $listParts];
+	}
+
+	protected static $libScssphpGlob = ['pattern'];
+	protected function libScssphpGlob($args)
+	{
+		$string = $this->coerceString($args[0]);
+		$pattern = $this->compileStringContent($string);
+		$matches = glob($pattern);
+		$listParts = [];
+
+		foreach ($matches as $match) {
+			if (! is_file($match)) {
+				continue;
+			}
+
+			$listParts[] = [Type::T_STRING, '"', [$match]];
+		}
+
+		return [Type::T_LIST, ',', $listParts];
+	}
 }

Spacing +189 added lines, -189 removed lines

@@ -233,7 +233,7 @@ 
             if (\is_array($cache) && isset($cache['dependencies']) && isset($cache['out'])) {
                 // check if any dependency file changed before accepting the cache
                 foreach ($cache['dependencies'] as $file => $mtime) {
-                    if (! is_file($file) || filemtime($file) !== $mtime) {
+                    if (!is_file($file) || filemtime($file) !== $mtime) {
                         unset($cache);
                         break;
                     }
@@ -284,7 +284,7 @@ 
 
         $out = $this->formatter->format($this->scope, $sourceMapGenerator);
 
-        if (! empty($out) && $this->sourceMap && $this->sourceMap !== self::SOURCE_MAP_NONE) {
+        if (!empty($out) && $this->sourceMap && $this->sourceMap !== self::SOURCE_MAP_NONE) {
             $sourceMap    = $sourceMapGenerator->generateJson();
             $sourceMapUrl = null;
 
@@ -465,22 +465,22 @@ 
             foreach ($block->selectors as $s) {
                 $selectors[] = $s;
 
-                if (! \is_array($s)) {
+                if (!\is_array($s)) {
                     continue;
                 }
 
                 // check extends
-                if (! empty($this->extendsMap)) {
+                if (!empty($this->extendsMap)) {
                     $this->matchExtends($s, $selectors);
 
                     // remove duplicates
-                    array_walk($selectors, function (&$value) {
+                    array_walk($selectors, function(&$value) {
                         $value = serialize($value);
                     });
 
                     $selectors = array_unique($selectors);
 
-                    array_walk($selectors, function (&$value) {
+                    array_walk($selectors, function(&$value) {
                         $value = unserialize($value);
                     });
                 }
@@ -573,7 +573,7 @@ 
             // if the new part is just including a previous part don't try to extend anymore
             if (\count($part) > 1) {
                 foreach ($partsPile as $previousPart) {
-                    if (! \count(array_diff($previousPart, $part))) {
+                    if (!\count(array_diff($previousPart, $part))) {
                         continue 2;
                     }
                 }
@@ -607,14 +607,14 @@ 
                         $slice = [];
 
                         foreach ($tempReplacement[$l] as $chunk) {
-                            if (! \in_array($chunk, $slice)) {
+                            if (!\in_array($chunk, $slice)) {
                                 $slice[] = $chunk;
                             }
                         }
 
                         array_unshift($replacement, $slice);
 
-                        if (! $this->isImmediateRelationshipCombinator(end($slice))) {
+                        if (!$this->isImmediateRelationshipCombinator(end($slice))) {
                             break;
                         }
                     }
@@ -647,7 +647,7 @@ 
                     }
 
                     // selector sequence merging
-                    if (! empty($before) && \count($new) > 1) {
+                    if (!empty($before) && \count($new) > 1) {
                         $preSharedParts = $k > 0 ? \array_slice($before, 0, $k) : [];
                         $postSharedParts = $k > 0 ? \array_slice($before, $k) : $before;
 
@@ -714,7 +714,7 @@ 
 
             if (
                 $this->isPseudoSelector($part, $matchesExtended) &&
-                \in_array($matchesExtended[1], [ 'slotted' ])
+                \in_array($matchesExtended[1], ['slotted'])
             ) {
                 $prev = end($out);
                 $prev = $this->glueFunctionSelectors($prev);
@@ -730,7 +730,7 @@ 
                         $extended = explode($matchesExtended[1] . '(', $matchesExtended[0], 2);
                         $extended[1] = $matchesPrev[2] . ', ' . $extended[1];
                         $extended = implode($matchesExtended[1] . '(', $extended);
-                        $extended = [ [ $extended ]];
+                        $extended = [[$extended]];
                         array_pop($out);
                     }
                 }
@@ -754,17 +754,17 @@ 
         $single = [];
 
         // simple usual cases, no need to do the whole trick
-        if (\in_array($rawSingle, [['>'],['+'],['~']])) {
+        if (\in_array($rawSingle, [['>'], ['+'], ['~']])) {
             return false;
         }
 
         foreach ($rawSingle as $part) {
             // matches Number
-            if (! \is_string($part)) {
+            if (!\is_string($part)) {
                 return false;
             }
 
-            if (! preg_match('/^[\[.:#%]/', $part) && \count($single)) {
+            if (!preg_match('/^[\[.:#%]/', $part) && \count($single)) {
                 $single[\count($single) - 1] .= $part;
             } else {
                 $single[] = $part;
@@ -791,7 +791,7 @@ 
             if (
                 $initial &&
                 $this->isPseudoSelector($part, $matches) &&
-                ! \in_array($matches[1], [ 'not' ])
+                !\in_array($matches[1], ['not'])
             ) {
                 $buffer    = $matches[2];
                 $parser    = $this->parserFactory(__METHOD__);
@@ -812,7 +812,7 @@ 
                             $subSelectorsExtended = implode(', ', $subSelectorsExtended);
                             $singleExtended = $single;
                             $singleExtended[$k] = str_replace('(' . $buffer . ')', "($subSelectorsExtended)", $part);
-                            $outOrigin[] = [ $singleExtended ];
+                            $outOrigin[] = [$singleExtended];
                             $found = true;
                         }
                     }
@@ -836,7 +836,7 @@ 
 
             foreach ($origin as $j => $new) {
                 // prevent infinite loop when target extends itself
-                if ($this->isSelfExtend($single, $origin) && ! $initial) {
+                if ($this->isSelfExtend($single, $origin) && !$initial) {
                     return false;
                 }
 
@@ -890,7 +890,7 @@ 
             $parents  = \array_slice($fragment, 0, $j);
             $slice    = end($parents);
 
-            if (empty($slice) || ! $this->isImmediateRelationshipCombinator($slice[0])) {
+            if (empty($slice) || !$this->isImmediateRelationshipCombinator($slice[0])) {
                 break;
             }
 
@@ -963,7 +963,7 @@ 
 
         $mediaQueries = $this->compileMediaQuery($this->multiplyMedia($this->env));
 
-        if (! empty($mediaQueries) && $mediaQueries) {
+        if (!empty($mediaQueries) && $mediaQueries) {
             $previousScope = $this->scope;
             $parentScope = $this->mediaParent($this->scope);
 
@@ -1046,8 +1046,8 @@ 
      */
     protected function mediaParent(OutputBlock $scope)
     {
-        while (! empty($scope->parent)) {
-            if (! empty($scope->type) && $scope->type !== Type::T_MEDIA) {
+        while (!empty($scope->parent)) {
+            if (!empty($scope->type) && $scope->type !== Type::T_MEDIA) {
                 break;
             }
 
@@ -1068,7 +1068,7 @@ 
         if (\is_array($directive)) {
             $s = '@' . $directive[0];
 
-            if (! empty($directive[1])) {
+            if (!empty($directive[1])) {
                 $s .= ' ' . $this->compileValue($directive[1]);
             }
 
@@ -1076,7 +1076,7 @@ 
         } else {
             $s = '@' . $directive->name;
 
-            if (! empty($directive->value)) {
+            if (!empty($directive->value)) {
                 $s .= ' ' . $this->compileValue($directive->value);
             }
 
@@ -1119,7 +1119,7 @@ 
         $selfParent = $block->selfParent;
 
         if (
-            ! $block->selfParent->selectors &&
+            !$block->selfParent->selectors &&
             isset($block->parent) && $block->parent &&
             isset($block->parent->selectors) && $block->parent->selectors
         ) {
@@ -1166,7 +1166,7 @@ 
         }
 
         for (;;) {
-            if (! $scope) {
+            if (!$scope) {
                 break;
             }
 
@@ -1192,7 +1192,7 @@ 
             }
         }
 
-        if (! \count($filteredScopes)) {
+        if (!\count($filteredScopes)) {
             return $this->rootBlock;
         }
 
@@ -1225,7 +1225,7 @@ 
      */
     protected function completeScope($scope, $previousScope)
     {
-        if (! $scope->type && (! $scope->selectors || ! \count($scope->selectors)) && \count($scope->lines)) {
+        if (!$scope->type && (!$scope->selectors || !\count($scope->selectors)) && \count($scope->lines)) {
             $scope->selectors = $this->findScopeSelectors($previousScope, $scope->depth);
         }
 
@@ -1328,7 +1328,7 @@ 
         $filtered = [];
 
         foreach ($envs as $e) {
-            if ($e->block && ! $this->isWith($e->block, $with, $without)) {
+            if ($e->block && !$this->isWith($e->block, $with, $without)) {
                 $ec = clone $e;
                 $ec->block     = null;
                 $ec->selectors = [];
@@ -1421,8 +1421,8 @@ 
 
         $envs = $this->compactEnv($env);
 
-        $this->env = $this->extractEnv(array_filter($envs, function (Environment $e) {
-            return ! isset($e->block->selectors);
+        $this->env = $this->extractEnv(array_filter($envs, function(Environment $e) {
+            return !isset($e->block->selectors);
         }));
 
         $this->scope = $this->makeOutputBlock($block->type, $selectors);
@@ -1734,7 +1734,7 @@ 
 
                 array_walk_recursive(
                     $node,
-                    function ($value, $key) use (&$compound) {
+                    function($value, $key) use (&$compound) {
                         $compound .= $value;
                     }
                 );
@@ -1817,7 +1817,7 @@ 
         foreach ($single as $part) {
             if (
                 empty($joined) ||
-                ! \is_string($part) ||
+                !\is_string($part) ||
                 preg_match('/[\[.:#%]/', $part)
             ) {
                 $joined[] = $part;
@@ -1843,7 +1843,7 @@ 
      */
     protected function compileSelector($selector)
     {
-        if (! \is_array($selector)) {
+        if (!\is_array($selector)) {
             return $selector; // media and the like
         }
 
@@ -1866,7 +1866,7 @@ 
     protected function compileSelectorPart($piece)
     {
         foreach ($piece as &$p) {
-            if (! \is_array($p)) {
+            if (!\is_array($p)) {
                 continue;
             }
 
@@ -1893,7 +1893,7 @@ 
      */
     protected function hasSelectorPlaceholder($selector)
     {
-        if (! \is_array($selector)) {
+        if (!\is_array($selector)) {
             return false;
         }
 
@@ -2095,13 +2095,13 @@ 
                         $newType = array_map([$this, 'compileValue'], \array_slice($q, 1));
 
                         // combining not and anything else than media type is too risky and should be avoided
-                        if (! $mediaTypeOnly) {
-                            if (\in_array(Type::T_NOT, $newType) || ($type && \in_array(Type::T_NOT, $type) )) {
+                        if (!$mediaTypeOnly) {
+                            if (\in_array(Type::T_NOT, $newType) || ($type && \in_array(Type::T_NOT, $type))) {
                                 if ($type) {
                                     array_unshift($parts, implode(' ', array_filter($type)));
                                 }
 
-                                if (! empty($parts)) {
+                                if (!empty($parts)) {
                                     if (\strlen($current)) {
                                         $current .= $this->formatter->tagSeparator;
                                     }
@@ -2164,7 +2164,7 @@ 
                 array_unshift($parts, implode(' ', array_filter($type)));
             }
 
-            if (! empty($parts)) {
+            if (!empty($parts)) {
                 if (\strlen($current)) {
                     $current .= $this->formatter->tagSeparator;
                 }
@@ -2178,7 +2178,7 @@ 
         }
 
         // no @media type except all, and no conflict?
-        if (! $out && $default) {
+        if (!$out && $default) {
             $out[] = $default;
         }
 
@@ -2202,7 +2202,7 @@ 
         $part1 = end($selectors1);
         $part2 = end($selectors2);
 
-        if (! $this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
+        if (!$this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
             return array_merge($selectors1, $selectors2);
         }
 
@@ -2212,7 +2212,7 @@ 
             $part1 = array_pop($selectors1);
             $part2 = array_pop($selectors2);
 
-            if (! $this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
+            if (!$this->isImmediateRelationshipCombinator($part1[0]) && $part1 !== $part2) {
                 if ($this->isImmediateRelationshipCombinator(reset($merged)[0])) {
                     array_unshift($merged, [$part1[0] . $part2[0]]);
                     $merged = array_merge($selectors1, $selectors2, $merged);
@@ -2224,7 +2224,7 @@ 
             }
 
             array_unshift($merged, $part1);
-        } while (! empty($selectors1) && ! empty($selectors2));
+        } while (!empty($selectors1) && !empty($selectors2));
 
         return $merged;
     }
@@ -2306,7 +2306,7 @@ 
             $path = $this->compileStringContent($rawPath);
 
             if (strpos($path, 'url(') !== 0 && $path = $this->findImport($path)) {
-                if (! $once || ! \in_array($path, $this->importedFiles)) {
+                if (!$once || !\in_array($path, $this->importedFiles)) {
                     $this->importFile($path, $out);
                     $this->importedFiles[] = $path;
                 }
@@ -2412,7 +2412,7 @@ 
         $i = 0;
 
         while ($i < \count($root->children)) {
-            if (! isset($root->children[$i]->type) || ! \in_array($root->children[$i]->type, $allowed)) {
+            if (!isset($root->children[$i]->type) || !\in_array($root->children[$i]->type, $allowed)) {
                 break;
             }
 
@@ -2460,7 +2460,7 @@ 
             if (
                 $lastChild->depth === $out->depth &&
                 \is_null($lastChild->selectors) &&
-                ! \count($lastChild->children)
+                !\count($lastChild->children)
             ) {
                 $outWrite = $lastChild;
             } else {
@@ -2494,7 +2494,7 @@ 
             $this->sourceIndex  = $child[1]->sourceIndex;
             $this->sourceLine   = $child[1]->sourceLine;
             $this->sourceColumn = $child[1]->sourceColumn;
-        } elseif (! empty($out->sourceLine) && ! empty($out->sourceName)) {
+        } elseif (!empty($out->sourceLine) && !empty($out->sourceName)) {
             $this->sourceLine   = $out->sourceLine;
             $this->sourceIndex  = array_search($out->sourceName, $this->sourceNames);
             $this->sourceColumn = $out->sourceColumn;
@@ -2534,7 +2534,7 @@ 
                 break;
 
             case Type::T_CHARSET:
-                if (! $this->charsetSeen) {
+                if (!$this->charsetSeen) {
                     $this->charsetSeen = true;
                     $this->appendRootDirective('@charset ' . $this->compileValue($child[1]) . ';', $out);
                 }
@@ -2581,7 +2581,7 @@ 
                         (\is_null($result = $this->get($name[1], false)) ||
                         $result === static::$null);
 
-                    if (! $isDefault || $shouldSet) {
+                    if (!$isDefault || $shouldSet) {
                         $this->set($name[1], $this->reduce($value), true, null, $value);
                     }
                     break;
@@ -2597,7 +2597,7 @@ 
                         $value = $this->get($value[1], true, null, true);
                     }
 
-                    $shorthandValue=&$value;
+                    $shorthandValue = &$value;
 
                     $shorthandDividerNeedsUnit = false;
                     $maxListElements           = null;
@@ -2613,7 +2613,7 @@ 
                     if ($compiledName === 'font' && $value[0] === Type::T_LIST && $value[1] === ',') {
                         // this is the case if more than one font is given: example: "font: 400 1em/1.3 arial,helvetica"
                         // we need to handle the first list element
-                        $shorthandValue=&$value[2][0];
+                        $shorthandValue = &$value[2][0];
                     }
 
                     if ($shorthandValue[0] === Type::T_EXPRESSION && $shorthandValue[1] === '/') {
@@ -2626,7 +2626,7 @@ 
                                 $divider = $this->reduce($divider, true);
                             }
 
-                            if (\intval($divider->dimension) && ! \count($divider->units)) {
+                            if (\intval($divider->dimension) && !\count($divider->units)) {
                                 $revert = false;
                             }
                         }
@@ -2650,7 +2650,7 @@ 
                                                 $divider = $this->reduce($divider, true);
                                             }
 
-                                            if (\intval($divider->dimension) && ! \count($divider->units)) {
+                                            if (\intval($divider->dimension) && !\count($divider->units)) {
                                                 $revert = false;
                                             }
                                         }
@@ -2716,7 +2716,7 @@ 
                         $result = current($result);
                         $selectors = $out->selectors;
 
-                        if (! $selectors && isset($child['selfParent'])) {
+                        if (!$selectors && isset($child['selfParent'])) {
                             $selectors = $this->multiplySelectors($this->env, $child['selfParent']);
                         }
 
@@ -2806,15 +2806,15 @@ 
                 $start = $this->reduce($for->start, true);
                 $end   = $this->reduce($for->end, true);
 
-                if (! $start instanceof Node\Number) {
+                if (!$start instanceof Node\Number) {
                     throw $this->error('%s is not a number', $start[0]);
                 }
 
-                if (! $end instanceof Node\Number) {
+                if (!$end instanceof Node\Number) {
                     throw $this->error('%s is not a number', $end[0]);
                 }
 
-                if (! ($start[2] == $end[2] || $end->unitless())) {
+                if (!($start[2] == $end[2] || $end->unitless())) {
                     throw $this->error('Incompatible units: "%s" && "%s".', $start->unitStr(), $end->unitStr());
                 }
 
@@ -2828,7 +2828,7 @@ 
 
                 for (;;) {
                     if (
-                        (! $for->until && $start - $d == $end) ||
+                        (!$for->until && $start - $d == $end) ||
                         ($for->until && $start == $end)
                     ) {
                         break;
@@ -2879,7 +2879,7 @@ 
 
                 $mixin = $this->get(static::$namespaces['mixin'] . $name, false);
 
-                if (! $mixin) {
+                if (!$mixin) {
                     throw $this->error("Undefined mixin $name");
                 }
 
@@ -2934,7 +2934,7 @@ 
 
                 $this->env->marker = 'mixin';
 
-                if (! empty($mixin->parentEnv)) {
+                if (!empty($mixin->parentEnv)) {
                     $this->env->declarationScopeParent = $mixin->parentEnv;
                 } else {
                     throw $this->error("@mixin $name() without parentEnv");
@@ -2951,7 +2951,7 @@ 
                 $argUsing   = $this->get(static::$namespaces['special'] . 'using', false, $env);
                 $argContent = $child[1];
 
-                if (! $content) {
+                if (!$content) {
                     break;
                 }
 
@@ -3119,9 +3119,9 @@ 
 
                 // special case: looks like css shorthand
                 if (
-                    $opName == 'div' && ! $inParens && ! $inExp && isset($right[2]) &&
+                    $opName == 'div' && !$inParens && !$inExp && isset($right[2]) &&
                     (($right[0] !== Type::T_NUMBER && $right[2] != '') ||
-                    ($right[0] === Type::T_NUMBER && ! $right->unitless()))
+                    ($right[0] === Type::T_NUMBER && !$right->unitless()))
                 ) {
                     return $this->expToString($value);
                 }
@@ -3153,7 +3153,7 @@ 
                     $coerceUnit = false;
 
                     if (
-                        ! isset($genOp) &&
+                        !isset($genOp) &&
                         $left[0] === Type::T_NUMBER && $right[0] === Type::T_NUMBER
                     ) {
                         $coerceUnit = true;
@@ -3286,7 +3286,7 @@ 
                 return $this->fncall($value[1], $value[2]);
 
             case Type::T_SELF:
-                $selfParent = ! empty($this->env->block->selfParent) ? $this->env->block->selfParent : null;
+                $selfParent = !empty($this->env->block->selfParent) ? $this->env->block->selfParent : null;
                 $selfSelector = $this->multiplySelectors($this->env, $selfParent);
                 $selfSelector = $this->collapseSelectors($selfSelector, true);
 
@@ -3344,10 +3344,10 @@ 
             // native PHP functions
             case 'user':
             case 'native':
-                list(,,$name, $fn, $prototype) = $functionReference;
+                list(,, $name, $fn, $prototype) = $functionReference;
                 $returnValue = $this->callNativeFunction($name, $fn, $prototype, $argValues);
 
-                if (! isset($returnValue)) {
+                if (!isset($returnValue)) {
                     return $this->fncall([Type::T_FUNCTION, $name, [Type::T_LIST, ',', []]], $argValues);
                 }
 
@@ -3471,7 +3471,7 @@ 
                     $value[2][$key] = $this->normalizeValue($item);
                 }
 
-                if (! empty($value['enclosing'])) {
+                if (!empty($value['enclosing'])) {
                     unset($value['enclosing']);
                 }
 
@@ -3612,8 +3612,8 @@ 
                   ($left === static::$false || $left === static::$true) &&
                   ($right === static::$false || $right === static::$true);
 
-        if (! $shouldEval) {
-            if (! $truthy) {
+        if (!$shouldEval) {
+            if (!$truthy) {
                 return null;
             }
         }
@@ -3640,8 +3640,8 @@ 
                   ($left === static::$false || $left === static::$true) &&
                   ($right === static::$false || $right === static::$true);
 
-        if (! $shouldEval) {
-            if (! $truthy) {
+        if (!$shouldEval) {
+            if (!$truthy) {
                 return null;
             }
         }
@@ -3921,10 +3921,10 @@ 
                 if (\count($value) === 5) {
                     $alpha = $this->compileRGBAValue($value[4], true);
 
-                    if (! is_numeric($alpha) || $alpha < 1) {
+                    if (!is_numeric($alpha) || $alpha < 1) {
                         $colorName = Colors::RGBaToColorName($r, $g, $b, $alpha);
 
-                        if (! \is_null($colorName)) {
+                        if (!\is_null($colorName)) {
                             return $colorName;
                         }
 
@@ -3938,13 +3938,13 @@ 
                     }
                 }
 
-                if (! is_numeric($r) || ! is_numeric($g) || ! is_numeric($b)) {
+                if (!is_numeric($r) || !is_numeric($g) || !is_numeric($b)) {
                     return 'rgb(' . $r . ', ' . $g . ', ' . $b . ')';
                 }
 
                 $colorName = Colors::RGBaToColorName($r, $g, $b);
 
-                if (! \is_null($colorName)) {
+                if (!\is_null($colorName)) {
                     return $colorName;
                 }
 
@@ -3973,8 +3973,8 @@ 
                         $value[1] = '"';
                     }
                     $content = str_replace(
-                        array('\\a', "\n", "\f" , '\\'  , "\r" , $value[1]),
-                        array("\r" , ' ' , '\\f', '\\\\', '\\a', '\\' . $value[1]),
+                        array('\\a', "\n", "\f", '\\', "\r", $value[1]),
+                        array("\r", ' ', '\\f', '\\\\', '\\a', '\\' . $value[1]),
                         $content
                     );
                 }
@@ -3982,12 +3982,12 @@ 
                 return $value[1] . $content . $value[1];
 
             case Type::T_FUNCTION:
-                $args = ! empty($value[2]) ? $this->compileValue($value[2]) : '';
+                $args = !empty($value[2]) ? $this->compileValue($value[2]) : '';
 
                 return "$value[1]($args)";
 
             case Type::T_FUNCTION_REFERENCE:
-                $name = ! empty($value[2]) ? $value[2] : '';
+                $name = !empty($value[2]) ? $value[2] : '';
 
                 return "get-function(\"$name\")";
 
@@ -4001,7 +4001,7 @@ 
                 list(, $delim, $items) = $value;
                 $pre = $post = '';
 
-                if (! empty($value['enclosing'])) {
+                if (!empty($value['enclosing'])) {
                     switch ($value['enclosing']) {
                         case 'parent':
                             //$pre = '(';
@@ -4052,7 +4052,7 @@ 
                     $filtered[$this->compileValue($keys[$i])] = $this->compileValue($values[$i]);
                 }
 
-                array_walk($filtered, function (&$value, $key) {
+                array_walk($filtered, function(&$value, $key) {
                     $value = $key . ': ' . $value;
                 });
 
@@ -4065,12 +4065,12 @@ 
 
                 $delim = $left[1];
 
-                if ($delim && $delim !== ' ' && ! $whiteLeft) {
+                if ($delim && $delim !== ' ' && !$whiteLeft) {
                     $delim .= ' ';
                 }
 
                 $left = \count($left[2]) > 0
-                    ?  $this->compileValue($left) . $delim . $whiteLeft
+                    ? $this->compileValue($left) . $delim . $whiteLeft
                     : '';
 
                 $delim = $right[1];
@@ -4235,7 +4235,7 @@ 
 
         $selfParentSelectors = null;
 
-        if (! \is_null($selfParent) && $selfParent->selectors) {
+        if (!\is_null($selfParent) && $selfParent->selectors) {
             $selfParentSelectors = $this->evalSelectors($selfParent->selectors);
         }
 
@@ -4273,7 +4273,7 @@ 
         $selectors = array_values($selectors);
 
         // case we are just starting a at-root : nothing to multiply but parentSelectors
-        if (! $selectors && $selfParentSelectors) {
+        if (!$selectors && $selfParentSelectors) {
             $selectors = $selfParentSelectors;
         }
 
@@ -4304,7 +4304,7 @@ 
                     $stillHasSelf = true;
                 }
 
-                if ($p === static::$selfSelector && ! $setSelf) {
+                if ($p === static::$selfSelector && !$setSelf) {
                     $setSelf = true;
 
                     if (\is_null($selfParentSelectors)) {
@@ -4321,7 +4321,7 @@ 
                             if (\is_array($pp)) {
                                 $flatten = [];
 
-                                array_walk_recursive($pp, function ($a) use (&$flatten) {
+                                array_walk_recursive($pp, function($a) use (&$flatten) {
                                     $flatten[] = $a;
                                 });
 
@@ -4353,8 +4353,8 @@ 
     protected function multiplyMedia(Environment $env = null, $childQueries = null)
     {
         if (
-            ! isset($env) ||
-            ! empty($env->block->type) && $env->block->type !== Type::T_MEDIA
+            !isset($env) ||
+            !empty($env->block->type) && $env->block->type !== Type::T_MEDIA
         ) {
             return $childQueries;
         }
@@ -4469,7 +4469,7 @@ 
     protected function backPropagateEnv($store, $excludedVars = null)
     {
         foreach ($store as $key => $value) {
-            if (empty($excludedVars) || ! \in_array($key, $excludedVars)) {
+            if (empty($excludedVars) || !\in_array($key, $excludedVars)) {
                 $this->set($key, $value, true);
             }
         }
@@ -4498,7 +4498,7 @@ 
     {
         $name = $this->normalizeName($name);
 
-        if (! isset($env)) {
+        if (!isset($env)) {
             $env = $this->getStoreEnv();
         }
 
@@ -4535,13 +4535,13 @@ 
                 break;
             }
 
-            if (! $hasNamespace && isset($env->marker)) {
-                if (! empty($env->store[$specialContentKey])) {
+            if (!$hasNamespace && isset($env->marker)) {
+                if (!empty($env->store[$specialContentKey])) {
                     $env = $env->store[$specialContentKey]->scope;
                     continue;
                 }
 
-                if (! empty($env->declarationScopeParent)) {
+                if (!empty($env->declarationScopeParent)) {
                     $env = $env->declarationScopeParent;
                     continue;
                 } else {
@@ -4601,7 +4601,7 @@ 
         $normalizedName = $this->normalizeName($name);
         $specialContentKey = static::$namespaces['special'] . 'content';
 
-        if (! isset($env)) {
+        if (!isset($env)) {
             $env = $this->getStoreEnv();
         }
 
@@ -4622,13 +4622,13 @@ 
                 return $env->store[$normalizedName];
             }
 
-            if (! $hasNamespace && isset($env->marker)) {
-                if (! empty($env->store[$specialContentKey])) {
+            if (!$hasNamespace && isset($env->marker)) {
+                if (!empty($env->store[$specialContentKey])) {
                     $env = $env->store[$specialContentKey]->scope;
                     continue;
                 }
 
-                if (! empty($env->declarationScopeParent)) {
+                if (!empty($env->declarationScopeParent)) {
                     $env = $env->declarationScopeParent;
                 } else {
                     $env = $this->rootEnv;
@@ -4663,7 +4663,7 @@ 
      */
     protected function has($name, Environment $env = null)
     {
-        return ! \is_null($this->get($name, false, $env));
+        return !\is_null($this->get($name, false, $env));
     }
 
     /**
@@ -4684,7 +4684,7 @@ 
                 $name = substr($name, 1);
             }
 
-            if (! $parser->parseValue($strValue, $value)) {
+            if (!$parser->parseValue($strValue, $value)) {
                 $value = $this->coerceValue($strValue);
             }
 
@@ -4763,7 +4763,7 @@ 
      */
     public function addImportPath($path)
     {
-        if (! \in_array($path, $this->importPaths)) {
+        if (!\in_array($path, $this->importPaths)) {
             $this->importPaths[] = $path;
         }
     }
@@ -4929,17 +4929,17 @@ 
         $hasExtension = preg_match('/[.]s?css$/', $url);
 
         // for "normal" scss imports (ignore vanilla css and external requests)
-        if (! preg_match('~\.css$|^https?://|^//~', $url)) {
+        if (!preg_match('~\.css$|^https?://|^//~', $url)) {
             $isPartial = (strpos(basename($url), '_') === 0);
 
             // try both normal and the _partial filename
             $urls = [$url . ($hasExtension ? '' : '.scss')];
 
-            if (! $isPartial) {
+            if (!$isPartial) {
                 $urls[] = preg_replace('~[^/]+$~', '_\0', $url) . ($hasExtension ? '' : '.scss');
             }
 
-            if (! $hasExtension) {
+            if (!$hasExtension) {
                 $urls[] = "$url/index.scss";
                 $urls[] = "$url/_index.scss";
                 // allow to find a plain css file, *if* no scss or partial scss is found
@@ -4952,7 +4952,7 @@ 
                 // check urls for normal import paths
                 foreach ($urls as $full) {
                     $separator = (
-                        ! empty($dir) &&
+                        !empty($dir) &&
                         substr($dir, -1) !== '/' &&
                         substr($full, 0, 1) !== '/'
                     ) ? '/' : '';
@@ -4966,14 +4966,14 @@ 
                 // check custom callback for import path
                 $file = \call_user_func($dir, $url);
 
-                if (! \is_null($file)) {
+                if (!\is_null($file)) {
                     return $file;
                 }
             }
         }
 
         if ($urls) {
-            if (! $hasExtension || preg_match('/[.]scss$/', $url)) {
+            if (!$hasExtension || preg_match('/[.]scss$/', $url)) {
                 throw $this->error("`$url` file not found for @import");
             }
         }
@@ -5061,7 +5061,7 @@ 
             $msg = sprintf($msg, ...$args);
         }
 
-        if (! $this->ignoreCallStackMessage) {
+        if (!$this->ignoreCallStackMessage) {
             $line   = $this->sourceLine;
             $column = $this->sourceColumn;
 
@@ -5138,7 +5138,7 @@ 
 
                     $callStackMsg[] = $msg;
 
-                    if (! \is_null($limit) && $ncall > $limit) {
+                    if (!\is_null($limit) && $ncall > $limit) {
                         break;
                     }
                 }
@@ -5158,7 +5158,7 @@ 
     protected function handleImportLoop($name)
     {
         for ($env = $this->env; $env; $env = $env->parent) {
-            if (! $env->block) {
+            if (!$env->block) {
                 continue;
             }
 
@@ -5180,7 +5180,7 @@ 
      */
     protected function callScssFunction($func, $argValues)
     {
-        if (! $func) {
+        if (!$func) {
             return static::$defaultValue;
         }
         $name = $func->name;
@@ -5199,7 +5199,7 @@ 
 
         $this->env->marker = 'function';
 
-        if (! empty($func->parentEnv)) {
+        if (!empty($func->parentEnv)) {
             $this->env->declarationScopeParent = $func->parentEnv;
         } else {
             throw $this->error("@function $name() without parentEnv");
@@ -5209,7 +5209,7 @@ 
 
         $this->popEnv();
 
-        return ! isset($ret) ? static::$defaultValue : $ret;
+        return !isset($ret) ? static::$defaultValue : $ret;
     }
 
     /**
@@ -5246,7 +5246,7 @@ 
 
         $returnValue = \call_user_func($function, $sorted, $kwargs);
 
-        if (! isset($returnValue)) {
+        if (!isset($returnValue)) {
             return null;
         }
 
@@ -5264,7 +5264,7 @@ 
     {
         $libName = 'lib' . preg_replace_callback(
             '/_(.)/',
-            function ($m) {
+            function($m) {
                 return ucfirst($m[1]);
             },
             ucfirst($name)
@@ -5286,7 +5286,7 @@ 
     {
         static $parser = null;
 
-        if (! isset($prototypes)) {
+        if (!isset($prototypes)) {
             $keyArgs = [];
             $posArgs = [];
 
@@ -5327,7 +5327,7 @@ 
 
         $finalArgs = [];
 
-        if (! \is_array(reset($prototypes))) {
+        if (!\is_array(reset($prototypes))) {
             $prototypes = [$prototypes];
         }
 
@@ -5388,7 +5388,7 @@ 
                 foreach ($prototype as $i => $p) {
                     $name = explode(':', $p)[0];
 
-                    if (! isset($finalArgs[$i])) {
+                    if (!isset($finalArgs[$i])) {
                         $finalArgs[$i] = null;
                     }
                 }
@@ -5421,7 +5421,7 @@ 
             $this->ignoreCallStackMessage = $ignoreCallStackMessage;
         }
 
-        if ($exceptionMessage && ! $prototypeHasMatch) {
+        if ($exceptionMessage && !$prototypeHasMatch) {
             if (\in_array($functionName, ['libRgb', 'libRgba', 'libHsl', 'libHsla'])) {
                 // if var() or calc() is used as an argument, return as a css function
                 foreach ($args as $arg) {
@@ -5484,12 +5484,12 @@ 
 
         // assign the keyword args
         foreach ((array) $argValues as $arg) {
-            if (! empty($arg[0])) {
+            if (!empty($arg[0])) {
                 $hasKeywordArgument = true;
 
                 $name = $arg[0][1];
 
-                if (! isset($args[$name])) {
+                if (!isset($args[$name])) {
                     foreach (array_keys($args) as $an) {
                         if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
                             $name = $an;
@@ -5498,7 +5498,7 @@ 
                     }
                 }
 
-                if (! isset($args[$name]) || $args[$name][3]) {
+                if (!isset($args[$name]) || $args[$name][3]) {
                     if ($hasVariable) {
                         $deferredNamedKeywordArgs[$name] = $arg[1];
                     } else {
@@ -5509,14 +5509,14 @@ 
                 } else {
                     $keywordArgs[$name] = $arg[1];
                 }
-            } elseif (! empty($arg[2])) {
+            } elseif (!empty($arg[2])) {
                 // $arg[2] means a var followed by ... in the arg ($list... )
                 $val = $this->reduce($arg[1], true);
 
                 if ($val[0] === Type::T_LIST) {
                     foreach ($val[2] as $name => $item) {
-                        if (! is_numeric($name)) {
-                            if (! isset($args[$name])) {
+                        if (!is_numeric($name)) {
+                            if (!isset($args[$name])) {
                                 foreach (array_keys($args) as $an) {
                                     if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
                                         $name = $an;
@@ -5543,8 +5543,8 @@ 
                         $name = $this->compileStringContent($this->coerceString($name));
                         $item = $val[2][$i];
 
-                        if (! is_numeric($name)) {
-                            if (! isset($args[$name])) {
+                        if (!is_numeric($name)) {
+                            if (!isset($args[$name])) {
                                 foreach (array_keys($args) as $an) {
                                     if (str_replace('_', '-', $an) === str_replace('_', '-', $name)) {
                                         $name = $an;
@@ -5588,7 +5588,7 @@ 
                     }
                 }
 
-                $val = [Type::T_LIST, \is_null($splatSeparator) ? ',' : $splatSeparator , [], $isVariable];
+                $val = [Type::T_LIST, \is_null($splatSeparator) ? ',' : $splatSeparator, [], $isVariable];
 
                 for ($count = \count($remaining); $i < $count; $i++) {
                     $val[2][] = $remaining[$i];
@@ -5605,7 +5605,7 @@ 
                 $val = $remaining[$i];
             } elseif (isset($keywordArgs[$name])) {
                 $val = $keywordArgs[$name];
-            } elseif (! empty($default)) {
+            } elseif (!empty($default)) {
                 continue;
             } else {
                 throw $this->error("Missing argument $name");
@@ -5753,7 +5753,7 @@ 
             return [Type::T_LIST, ',', $list];
         }
 
-        return [Type::T_LIST, $delim, ! isset($item) ? [] : [$item]];
+        return [Type::T_LIST, $delim, !isset($item) ? [] : [$item]];
     }
 
     /**
@@ -5784,10 +5784,10 @@ 
         switch ($value[0]) {
             case Type::T_COLOR:
                 for ($i = 1; $i <= 3; $i++) {
-                    if (! is_numeric($value[$i])) {
+                    if (!is_numeric($value[$i])) {
                         $cv = $this->compileRGBAValue($value[$i]);
 
-                        if (! is_numeric($cv)) {
+                        if (!is_numeric($cv)) {
                             return null;
                         }
 
@@ -5795,10 +5795,10 @@ 
                     }
 
                     if (isset($value[4])) {
-                        if (! is_numeric($value[4])) {
+                        if (!is_numeric($value[4])) {
                             $cv = $this->compileRGBAValue($value[4], true);
 
-                            if (! is_numeric($cv)) {
+                            if (!is_numeric($cv)) {
                                 return null;
                             }
 
@@ -5822,7 +5822,7 @@ 
                 return null;
 
             case Type::T_KEYWORD:
-                if (! \is_string($value[1])) {
+                if (!\is_string($value[1])) {
                     return null;
                 }
 
@@ -5915,7 +5915,7 @@ 
      */
     protected function compileColorPartValue($value, $min, $max, $isInt = true, $clamp = true, $modulo = false)
     {
-        if (! is_numeric($value)) {
+        if (!is_numeric($value)) {
             if (\is_array($value)) {
                 $reduced = $this->reduce($value);
 
@@ -5996,7 +5996,7 @@ 
     protected function coercePercent($value)
     {
         if ($value[0] === Type::T_NUMBER) {
-            if (! empty($value[2]['%'])) {
+            if (!empty($value[2]['%'])) {
                 return $value[1] / 100;
             }
 
@@ -6234,7 +6234,7 @@ 
             return static::$null;
         }
 
-        if (! in_array($functionReference[0], [Type::T_FUNCTION_REFERENCE, Type::T_FUNCTION])) {
+        if (!in_array($functionReference[0], [Type::T_FUNCTION_REFERENCE, Type::T_FUNCTION])) {
             throw $this->error('Function reference expected, got ' . $functionReference[0]);
         }
 
@@ -6245,7 +6245,7 @@ 
             if (is_numeric($varname)) {
                 $varname = null;
             } else {
-                $varname = [ 'var', $varname];
+                $varname = ['var', $varname];
             }
 
             $callArgs[] = [$varname, $arg, false];
@@ -6281,7 +6281,7 @@ 
     {
         list($cond, $t, $f) = $args;
 
-        if (! $this->isTruthy($this->reduce($cond, true))) {
+        if (!$this->isTruthy($this->reduce($cond, true))) {
             return $this->reduce($f, true);
         }
 
@@ -6322,12 +6322,12 @@ 
         ['color', 'alpha'],
         ['channels'],
         ['red', 'green', 'blue'],
-        ['red', 'green', 'blue', 'alpha'] ];
+        ['red', 'green', 'blue', 'alpha']];
     protected function libRgb($args, $kwargs, $funcName = 'rgb')
     {
         switch (\count($args)) {
             case 1:
-                if (! $color = $this->coerceColor($args[0], true)) {
+                if (!$color = $this->coerceColor($args[0], true)) {
                     $color = [Type::T_STRING, '', [$funcName . '(', $args[0], ')']];
                 }
                 break;
@@ -6335,7 +6335,7 @@ 
             case 3:
                 $color = [Type::T_COLOR, $args[0], $args[1], $args[2]];
 
-                if (! $color = $this->coerceColor($color)) {
+                if (!$color = $this->coerceColor($color)) {
                     $color = [Type::T_STRING, '', [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ')']];
                 }
 
@@ -6360,7 +6360,7 @@ 
             default:
                 $color = [Type::T_COLOR, $args[0], $args[1], $args[2], $args[3]];
 
-                if (! $color = $this->coerceColor($color)) {
+                if (!$color = $this->coerceColor($color)) {
                     $color = [Type::T_STRING, '',
                         [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ', ', $args[3], ')']];
                 }
@@ -6375,7 +6375,7 @@ 
         ['color', 'alpha'],
         ['channels'],
         ['red', 'green', 'blue'],
-        ['red', 'green', 'blue', 'alpha'] ];
+        ['red', 'green', 'blue', 'alpha']];
     protected function libRgba($args, $kwargs)
     {
         return $this->libRgb($args, $kwargs, 'rgba');
@@ -6390,7 +6390,7 @@ 
             if (isset($args[$iarg])) {
                 $val = $this->assertNumber($args[$iarg]);
 
-                if (! isset($color[$irgba])) {
+                if (!isset($color[$irgba])) {
                     $color[$irgba] = (($irgba < 4) ? 0 : 1);
                 }
 
@@ -6398,11 +6398,11 @@ 
             }
         }
 
-        if (! empty($args[4]) || ! empty($args[5]) || ! empty($args[6])) {
+        if (!empty($args[4]) || !empty($args[5]) || !empty($args[6])) {
             $hsl = $this->toHSL($color[1], $color[2], $color[3]);
 
             foreach ([4 => 1, 5 => 2, 6 => 3] as $iarg => $ihsl) {
-                if (! empty($args[$iarg])) {
+                if (!empty($args[$iarg])) {
                     $val = $this->assertNumber($args[$iarg]);
                     $hsl[$ihsl] = \call_user_func($fn, $hsl[$ihsl], $val, $iarg);
                 }
@@ -6426,7 +6426,7 @@ 
     ];
     protected function libAdjustColor($args)
     {
-        return $this->alterColor($args, function ($base, $alter, $i) {
+        return $this->alterColor($args, function($base, $alter, $i) {
             return $base + $alter;
         });
     }
@@ -6437,7 +6437,7 @@ 
     ];
     protected function libChangeColor($args)
     {
-        return $this->alterColor($args, function ($base, $alter, $i) {
+        return $this->alterColor($args, function($base, $alter, $i) {
             return $alter;
         });
     }
@@ -6448,7 +6448,7 @@ 
     ];
     protected function libScaleColor($args)
     {
-        return $this->alterColor($args, function ($base, $scale, $i) {
+        return $this->alterColor($args, function($base, $scale, $i) {
             // 1, 2, 3 - rgb
             // 4, 5, 6 - hsl
             // 7 - a
@@ -6566,7 +6566,7 @@ 
         $first = $this->assertColor($first);
         $second = $this->assertColor($second);
 
-        if (! isset($weight)) {
+        if (!isset($weight)) {
             $weight = 0.5;
         } else {
             $weight = $this->coercePercent($weight);
@@ -6597,7 +6597,7 @@ 
     protected static $libHsl = [
         ['channels'],
         ['hue', 'saturation', 'lightness'],
-        ['hue', 'saturation', 'lightness', 'alpha'] ];
+        ['hue', 'saturation', 'lightness', 'alpha']];
     protected function libHsl($args, $kwargs, $funcName = 'hsl')
     {
         $args_to_check = $args;
@@ -6634,7 +6634,7 @@ 
             if (
                 $k >= 2 && count($args) === 4 &&
                 in_array($arg[0], [Type::T_FUNCTION_CALL, Type::T_FUNCTION]) &&
-                in_array($arg[1], ['calc','env'])
+                in_array($arg[1], ['calc', 'env'])
             ) {
                 return null;
             }
@@ -6645,19 +6645,19 @@ 
         if (\count($args) === 4) {
             $alpha = $this->compileColorPartValue($args[3], 0, 100, false);
 
-            if (! is_numeric($hue) || ! is_numeric($saturation) || ! is_numeric($lightness) || ! is_numeric($alpha)) {
+            if (!is_numeric($hue) || !is_numeric($saturation) || !is_numeric($lightness) || !is_numeric($alpha)) {
                 return [Type::T_STRING, '',
                     [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ', ', $args[3], ')']];
             }
         } else {
-            if (! is_numeric($hue) || ! is_numeric($saturation) || ! is_numeric($lightness)) {
+            if (!is_numeric($hue) || !is_numeric($saturation) || !is_numeric($lightness)) {
                 return [Type::T_STRING, '', [$funcName . '(', $args[0], ', ', $args[1], ', ', $args[2], ')']];
             }
         }
 
         $color = $this->toRGB($hue, $saturation, $lightness);
 
-        if (! \is_null($alpha)) {
+        if (!\is_null($alpha)) {
             $color[4] = $alpha;
         }
 
@@ -6792,7 +6792,7 @@ 
     {
         list($value, $weight) = $args;
 
-        if (! isset($weight)) {
+        if (!isset($weight)) {
             $weight = 1;
         } else {
             $weight = $this->coercePercent($weight);
@@ -6870,7 +6870,7 @@ 
     {
         $value = $args[0];
 
-        if ($value[0] === Type::T_STRING && ! empty($value[1])) {
+        if ($value[0] === Type::T_STRING && !empty($value[1])) {
             return $value;
         }
 
@@ -6984,7 +6984,7 @@ 
             if (empty($unit)) {
                 $unit = $number[2];
                 $originalUnit = $item->unitStr();
-            } elseif ($number[1] && $unit !== $number[2] && ! empty($number[2])) {
+            } elseif ($number[1] && $unit !== $number[2] && !empty($number[2])) {
                 throw $this->error('Incompatible units: "%s" and "%s".', $originalUnit, $item->unitStr());
             }
 
@@ -7049,7 +7049,7 @@ 
             $n += \count($list[2]);
         }
 
-        if (! isset($list[2][$n])) {
+        if (!isset($list[2][$n])) {
             throw $this->error('Invalid argument for "n"');
         }
 
@@ -7064,7 +7064,7 @@ 
         $map = $this->assertMap($args[0]);
         $key = $args[1];
 
-        if (! \is_null($key)) {
+        if (!\is_null($key)) {
             $key = $this->compileStringContent($this->coerceString($key));
 
             for ($i = \count($map[1]) - 1; $i >= 0; $i--) {
@@ -7180,7 +7180,7 @@ 
         $list = $args[0];
         $this->coerceList($list, ' ');
 
-        if (! empty($list['enclosing']) && $list['enclosing'] === 'bracket') {
+        if (!empty($list['enclosing']) && $list['enclosing'] === 'bracket') {
             return true;
         }
 
@@ -7189,7 +7189,7 @@ 
 
     protected function listSeparatorForJoin($list1, $sep)
     {
-        if (! isset($sep)) {
+        if (!isset($sep)) {
             return $list1[1];
         }
 
@@ -7224,7 +7224,7 @@ 
             $bracketed = false;
         } else {
             $bracketed = $this->compileValue($bracketed);
-            $bracketed = ! ! $bracketed;
+            $bracketed = !!$bracketed;
 
             if ($bracketed === true) {
                 $bracketed = true;
@@ -7234,7 +7234,7 @@ 
         if ($bracketed === 'auto') {
             $bracketed = false;
 
-            if (! empty($list1['enclosing']) && $list1['enclosing'] === 'bracket') {
+            if (!empty($list1['enclosing']) && $list1['enclosing'] === 'bracket') {
                 $bracketed = true;
             }
         }
@@ -7356,8 +7356,8 @@ 
         list($number1, $number2) = $args;
 
         if (
-            ! isset($number1[0]) || $number1[0] !== Type::T_NUMBER ||
-            ! isset($number2[0]) || $number2[0] !== Type::T_NUMBER
+            !isset($number1[0]) || $number1[0] !== Type::T_NUMBER ||
+            !isset($number2[0]) || $number2[0] !== Type::T_NUMBER
         ) {
             throw $this->error('Invalid argument(s) for "comparable"');
         }
@@ -7410,7 +7410,7 @@ 
     protected static $libStrSlice = ['string', 'start-at', 'end-at:-1'];
     protected function libStrSlice($args)
     {
-        if (isset($args[2]) && ! $args[2][1]) {
+        if (isset($args[2]) && !$args[2][1]) {
             return static::$nullString;
         }
 
@@ -7554,7 +7554,7 @@ 
     {
         static $id;
 
-        if (! isset($id)) {
+        if (!isset($id)) {
             $id = PHP_INT_SIZE === 4
                 ? mt_rand(0, pow(36, 5)) . str_pad(mt_rand(0, pow(36, 5)) % 10000000, 7, '0', STR_PAD_LEFT)
                 : mt_rand(0, pow(36, 8));
@@ -7581,10 +7581,10 @@ 
             }
 
             if (
-                ! empty($value['enclosing']) &&
+                !empty($value['enclosing']) &&
                 ($force_enclosing_display ||
                     ($value['enclosing'] === 'bracket') ||
-                    ! \count($value[2]))
+                    !\count($value[2]))
             ) {
                 $value['enclosing'] = 'forced_' . $value['enclosing'];
                 $force_enclosing_display = true;
@@ -7674,11 +7674,11 @@ 
     protected function isSuperSelector($super, $sub)
     {
         // one and only one selector for each arg
-        if (! $super || \count($super) !== 1) {
+        if (!$super || \count($super) !== 1) {
             throw $this->error('Invalid super selector for isSuperSelector()');
         }
 
-        if (! $sub || \count($sub) !== 1) {
+        if (!$sub || \count($sub) !== 1) {
             throw $this->error('Invalid sub selector for isSuperSelector()');
         }
 
@@ -7693,7 +7693,7 @@ 
 
             array_walk_recursive(
                 $node,
-                function ($value, $key) use (&$compound) {
+                function($value, $key) use (&$compound) {
                     $compound .= $value;
                 }
             );
@@ -7706,7 +7706,7 @@ 
                 $nextMustMatch = true;
                 $i++;
             } else {
-                while ($i < \count($sub) && ! $this->isSuperPart($node, $sub[$i])) {
+                while ($i < \count($sub) && !$this->isSuperPart($node, $sub[$i])) {
                     if ($nextMustMatch) {
                         return false;
                     }
@@ -7782,14 +7782,14 @@ 
     {
         $lastSelectors = array_pop($selectors);
 
-        if (! $lastSelectors) {
+        if (!$lastSelectors) {
             throw $this->error('Invalid selector list in selector-append()');
         }
 
         while (\count($selectors)) {
             $previousSelectors = array_pop($selectors);
 
-            if (! $previousSelectors) {
+            if (!$previousSelectors) {
                 throw $this->error('Invalid selector list in selector-append()');
             }
 
@@ -7832,7 +7832,7 @@ 
         $extendee  = $this->getSelectorArg($extendee);
         $extender  = $this->getSelectorArg($extender);
 
-        if (! $selectors || ! $extendee || ! $extender) {
+        if (!$selectors || !$extendee || !$extender) {
             throw $this->error('selector-extend() invalid arguments');
         }
 
@@ -7853,7 +7853,7 @@ 
         $original    = $this->getSelectorArg($original);
         $replacement = $this->getSelectorArg($replacement);
 
-        if (! $selectors || ! $original || ! $replacement) {
+        if (!$selectors || !$original || !$replacement) {
             throw $this->error('selector-replace() invalid arguments');
         }
 
@@ -7889,7 +7889,7 @@ 
         $extended = [];
 
         foreach ($selectors as $selector) {
-            if (! $replace) {
+            if (!$replace) {
                 $extended[] = $selector;
             }
 
@@ -7957,7 +7957,7 @@ 
         $selectors1 = $this->getSelectorArg($selectors1);
         $selectors2 = $this->getSelectorArg($selectors2);
 
-        if (! $selectors1 || ! $selectors2) {
+        if (!$selectors1 || !$selectors2) {
             throw $this->error('selector-unify() invalid arguments');
         }
 
@@ -7982,11 +7982,11 @@ 
      */
     protected function unifyCompoundSelectors($compound1, $compound2)
     {
-        if (! \count($compound1)) {
+        if (!\count($compound1)) {
             return $compound2;
         }
 
-        if (! \count($compound2)) {
+        if (!\count($compound2)) {
             return $compound1;
         }
 
@@ -7995,7 +7995,7 @@ 
         $lastPart2 = array_pop($compound2);
         $last      = $this->mergeParts($lastPart1, $lastPart2);
 
-        if (! $last) {
+        if (!$last) {
             return [[]];
         }
 
@@ -8219,7 +8219,7 @@ 
     protected function findTagName($parts)
     {
         foreach ($parts as $part) {
-            if (! preg_match('/^[\[.:#%_-]/', $part)) {
+            if (!preg_match('/^[\[.:#%_-]/', $part)) {
                 return $part;
             }
         }
@@ -8257,7 +8257,7 @@ 
         $listParts = [];
 
         foreach ($matches as $match) {
-            if (! is_file($match)) {
+            if (!is_file($match)) {
                 continue;
             }
 

SCSS/vendor/scssphp/scssphp/src/Colors.php

Indentation +211 added lines, -211 removed lines

@@ -19,227 +19,227 @@
  */
 class Colors
 {
-    /**
-     * CSS Colors
-     *
-     * @see http://www.w3.org/TR/css3-color
-     *
-     * @var array
-     */
-    protected static $cssColors = [
-        'aliceblue' => '240,248,255',
-        'antiquewhite' => '250,235,215',
-        'cyan' => '0,255,255',
-        'aqua' => '0,255,255',
-        'aquamarine' => '127,255,212',
-        'azure' => '240,255,255',
-        'beige' => '245,245,220',
-        'bisque' => '255,228,196',
-        'black' => '0,0,0',
-        'blanchedalmond' => '255,235,205',
-        'blue' => '0,0,255',
-        'blueviolet' => '138,43,226',
-        'brown' => '165,42,42',
-        'burlywood' => '222,184,135',
-        'cadetblue' => '95,158,160',
-        'chartreuse' => '127,255,0',
-        'chocolate' => '210,105,30',
-        'coral' => '255,127,80',
-        'cornflowerblue' => '100,149,237',
-        'cornsilk' => '255,248,220',
-        'crimson' => '220,20,60',
-        'darkblue' => '0,0,139',
-        'darkcyan' => '0,139,139',
-        'darkgoldenrod' => '184,134,11',
-        'darkgray' => '169,169,169',
-        'darkgrey' => '169,169,169',
-        'darkgreen' => '0,100,0',
-        'darkkhaki' => '189,183,107',
-        'darkmagenta' => '139,0,139',
-        'darkolivegreen' => '85,107,47',
-        'darkorange' => '255,140,0',
-        'darkorchid' => '153,50,204',
-        'darkred' => '139,0,0',
-        'darksalmon' => '233,150,122',
-        'darkseagreen' => '143,188,143',
-        'darkslateblue' => '72,61,139',
-        'darkslategray' => '47,79,79',
-        'darkslategrey' => '47,79,79',
-        'darkturquoise' => '0,206,209',
-        'darkviolet' => '148,0,211',
-        'deeppink' => '255,20,147',
-        'deepskyblue' => '0,191,255',
-        'dimgray' => '105,105,105',
-        'dimgrey' => '105,105,105',
-        'dodgerblue' => '30,144,255',
-        'firebrick' => '178,34,34',
-        'floralwhite' => '255,250,240',
-        'forestgreen' => '34,139,34',
-        'magenta' => '255,0,255',
-        'fuchsia' => '255,0,255',
-        'gainsboro' => '220,220,220',
-        'ghostwhite' => '248,248,255',
-        'gold' => '255,215,0',
-        'goldenrod' => '218,165,32',
-        'gray' => '128,128,128',
-        'grey' => '128,128,128',
-        'green' => '0,128,0',
-        'greenyellow' => '173,255,47',
-        'honeydew' => '240,255,240',
-        'hotpink' => '255,105,180',
-        'indianred' => '205,92,92',
-        'indigo' => '75,0,130',
-        'ivory' => '255,255,240',
-        'khaki' => '240,230,140',
-        'lavender' => '230,230,250',
-        'lavenderblush' => '255,240,245',
-        'lawngreen' => '124,252,0',
-        'lemonchiffon' => '255,250,205',
-        'lightblue' => '173,216,230',
-        'lightcoral' => '240,128,128',
-        'lightcyan' => '224,255,255',
-        'lightgoldenrodyellow' => '250,250,210',
-        'lightgray' => '211,211,211',
-        'lightgrey' => '211,211,211',
-        'lightgreen' => '144,238,144',
-        'lightpink' => '255,182,193',
-        'lightsalmon' => '255,160,122',
-        'lightseagreen' => '32,178,170',
-        'lightskyblue' => '135,206,250',
-        'lightslategray' => '119,136,153',
-        'lightslategrey' => '119,136,153',
-        'lightsteelblue' => '176,196,222',
-        'lightyellow' => '255,255,224',
-        'lime' => '0,255,0',
-        'limegreen' => '50,205,50',
-        'linen' => '250,240,230',
-        'maroon' => '128,0,0',
-        'mediumaquamarine' => '102,205,170',
-        'mediumblue' => '0,0,205',
-        'mediumorchid' => '186,85,211',
-        'mediumpurple' => '147,112,219',
-        'mediumseagreen' => '60,179,113',
-        'mediumslateblue' => '123,104,238',
-        'mediumspringgreen' => '0,250,154',
-        'mediumturquoise' => '72,209,204',
-        'mediumvioletred' => '199,21,133',
-        'midnightblue' => '25,25,112',
-        'mintcream' => '245,255,250',
-        'mistyrose' => '255,228,225',
-        'moccasin' => '255,228,181',
-        'navajowhite' => '255,222,173',
-        'navy' => '0,0,128',
-        'oldlace' => '253,245,230',
-        'olive' => '128,128,0',
-        'olivedrab' => '107,142,35',
-        'orange' => '255,165,0',
-        'orangered' => '255,69,0',
-        'orchid' => '218,112,214',
-        'palegoldenrod' => '238,232,170',
-        'palegreen' => '152,251,152',
-        'paleturquoise' => '175,238,238',
-        'palevioletred' => '219,112,147',
-        'papayawhip' => '255,239,213',
-        'peachpuff' => '255,218,185',
-        'peru' => '205,133,63',
-        'pink' => '255,192,203',
-        'plum' => '221,160,221',
-        'powderblue' => '176,224,230',
-        'purple' => '128,0,128',
-        'red' => '255,0,0',
-        'rosybrown' => '188,143,143',
-        'royalblue' => '65,105,225',
-        'saddlebrown' => '139,69,19',
-        'salmon' => '250,128,114',
-        'sandybrown' => '244,164,96',
-        'seagreen' => '46,139,87',
-        'seashell' => '255,245,238',
-        'sienna' => '160,82,45',
-        'silver' => '192,192,192',
-        'skyblue' => '135,206,235',
-        'slateblue' => '106,90,205',
-        'slategray' => '112,128,144',
-        'slategrey' => '112,128,144',
-        'snow' => '255,250,250',
-        'springgreen' => '0,255,127',
-        'steelblue' => '70,130,180',
-        'tan' => '210,180,140',
-        'teal' => '0,128,128',
-        'thistle' => '216,191,216',
-        'tomato' => '255,99,71',
-        'turquoise' => '64,224,208',
-        'violet' => '238,130,238',
-        'wheat' => '245,222,179',
-        'white' => '255,255,255',
-        'whitesmoke' => '245,245,245',
-        'yellow' => '255,255,0',
-        'yellowgreen' => '154,205,50',
-        'rebeccapurple' => '102,51,153',
-        'transparent' => '0,0,0,0',
-    ];
+	/**
+	 * CSS Colors
+	 *
+	 * @see http://www.w3.org/TR/css3-color
+	 *
+	 * @var array
+	 */
+	protected static $cssColors = [
+		'aliceblue' => '240,248,255',
+		'antiquewhite' => '250,235,215',
+		'cyan' => '0,255,255',
+		'aqua' => '0,255,255',
+		'aquamarine' => '127,255,212',
+		'azure' => '240,255,255',
+		'beige' => '245,245,220',
+		'bisque' => '255,228,196',
+		'black' => '0,0,0',
+		'blanchedalmond' => '255,235,205',
+		'blue' => '0,0,255',
+		'blueviolet' => '138,43,226',
+		'brown' => '165,42,42',
+		'burlywood' => '222,184,135',
+		'cadetblue' => '95,158,160',
+		'chartreuse' => '127,255,0',
+		'chocolate' => '210,105,30',
+		'coral' => '255,127,80',
+		'cornflowerblue' => '100,149,237',
+		'cornsilk' => '255,248,220',
+		'crimson' => '220,20,60',
+		'darkblue' => '0,0,139',
+		'darkcyan' => '0,139,139',
+		'darkgoldenrod' => '184,134,11',
+		'darkgray' => '169,169,169',
+		'darkgrey' => '169,169,169',
+		'darkgreen' => '0,100,0',
+		'darkkhaki' => '189,183,107',
+		'darkmagenta' => '139,0,139',
+		'darkolivegreen' => '85,107,47',
+		'darkorange' => '255,140,0',
+		'darkorchid' => '153,50,204',
+		'darkred' => '139,0,0',
+		'darksalmon' => '233,150,122',
+		'darkseagreen' => '143,188,143',
+		'darkslateblue' => '72,61,139',
+		'darkslategray' => '47,79,79',
+		'darkslategrey' => '47,79,79',
+		'darkturquoise' => '0,206,209',
+		'darkviolet' => '148,0,211',
+		'deeppink' => '255,20,147',
+		'deepskyblue' => '0,191,255',
+		'dimgray' => '105,105,105',
+		'dimgrey' => '105,105,105',
+		'dodgerblue' => '30,144,255',
+		'firebrick' => '178,34,34',
+		'floralwhite' => '255,250,240',
+		'forestgreen' => '34,139,34',
+		'magenta' => '255,0,255',
+		'fuchsia' => '255,0,255',
+		'gainsboro' => '220,220,220',
+		'ghostwhite' => '248,248,255',
+		'gold' => '255,215,0',
+		'goldenrod' => '218,165,32',
+		'gray' => '128,128,128',
+		'grey' => '128,128,128',
+		'green' => '0,128,0',
+		'greenyellow' => '173,255,47',
+		'honeydew' => '240,255,240',
+		'hotpink' => '255,105,180',
+		'indianred' => '205,92,92',
+		'indigo' => '75,0,130',
+		'ivory' => '255,255,240',
+		'khaki' => '240,230,140',
+		'lavender' => '230,230,250',
+		'lavenderblush' => '255,240,245',
+		'lawngreen' => '124,252,0',
+		'lemonchiffon' => '255,250,205',
+		'lightblue' => '173,216,230',
+		'lightcoral' => '240,128,128',
+		'lightcyan' => '224,255,255',
+		'lightgoldenrodyellow' => '250,250,210',
+		'lightgray' => '211,211,211',
+		'lightgrey' => '211,211,211',
+		'lightgreen' => '144,238,144',
+		'lightpink' => '255,182,193',
+		'lightsalmon' => '255,160,122',
+		'lightseagreen' => '32,178,170',
+		'lightskyblue' => '135,206,250',
+		'lightslategray' => '119,136,153',
+		'lightslategrey' => '119,136,153',
+		'lightsteelblue' => '176,196,222',
+		'lightyellow' => '255,255,224',
+		'lime' => '0,255,0',
+		'limegreen' => '50,205,50',
+		'linen' => '250,240,230',
+		'maroon' => '128,0,0',
+		'mediumaquamarine' => '102,205,170',
+		'mediumblue' => '0,0,205',
+		'mediumorchid' => '186,85,211',
+		'mediumpurple' => '147,112,219',
+		'mediumseagreen' => '60,179,113',
+		'mediumslateblue' => '123,104,238',
+		'mediumspringgreen' => '0,250,154',
+		'mediumturquoise' => '72,209,204',
+		'mediumvioletred' => '199,21,133',
+		'midnightblue' => '25,25,112',
+		'mintcream' => '245,255,250',
+		'mistyrose' => '255,228,225',
+		'moccasin' => '255,228,181',
+		'navajowhite' => '255,222,173',
+		'navy' => '0,0,128',
+		'oldlace' => '253,245,230',
+		'olive' => '128,128,0',
+		'olivedrab' => '107,142,35',
+		'orange' => '255,165,0',
+		'orangered' => '255,69,0',
+		'orchid' => '218,112,214',
+		'palegoldenrod' => '238,232,170',
+		'palegreen' => '152,251,152',
+		'paleturquoise' => '175,238,238',
+		'palevioletred' => '219,112,147',
+		'papayawhip' => '255,239,213',
+		'peachpuff' => '255,218,185',
+		'peru' => '205,133,63',
+		'pink' => '255,192,203',
+		'plum' => '221,160,221',
+		'powderblue' => '176,224,230',
+		'purple' => '128,0,128',
+		'red' => '255,0,0',
+		'rosybrown' => '188,143,143',
+		'royalblue' => '65,105,225',
+		'saddlebrown' => '139,69,19',
+		'salmon' => '250,128,114',
+		'sandybrown' => '244,164,96',
+		'seagreen' => '46,139,87',
+		'seashell' => '255,245,238',
+		'sienna' => '160,82,45',
+		'silver' => '192,192,192',
+		'skyblue' => '135,206,235',
+		'slateblue' => '106,90,205',
+		'slategray' => '112,128,144',
+		'slategrey' => '112,128,144',
+		'snow' => '255,250,250',
+		'springgreen' => '0,255,127',
+		'steelblue' => '70,130,180',
+		'tan' => '210,180,140',
+		'teal' => '0,128,128',
+		'thistle' => '216,191,216',
+		'tomato' => '255,99,71',
+		'turquoise' => '64,224,208',
+		'violet' => '238,130,238',
+		'wheat' => '245,222,179',
+		'white' => '255,255,255',
+		'whitesmoke' => '245,245,245',
+		'yellow' => '255,255,0',
+		'yellowgreen' => '154,205,50',
+		'rebeccapurple' => '102,51,153',
+		'transparent' => '0,0,0,0',
+	];
 
-    /**
-     * Convert named color in a [r,g,b[,a]] array
-     *
-     * @param string $colorName
-     *
-     * @return array|null
-     */
-    public static function colorNameToRGBa($colorName)
-    {
-        if (\is_string($colorName) && isset(static::$cssColors[$colorName])) {
-            $rgba = explode(',', static::$cssColors[$colorName]);
+	/**
+	 * Convert named color in a [r,g,b[,a]] array
+	 *
+	 * @param string $colorName
+	 *
+	 * @return array|null
+	 */
+	public static function colorNameToRGBa($colorName)
+	{
+		if (\is_string($colorName) && isset(static::$cssColors[$colorName])) {
+			$rgba = explode(',', static::$cssColors[$colorName]);
 
-            // only case with opacity is transparent, with opacity=0, so we can intval on opacity also
-            $rgba = array_map('intval', $rgba);
+			// only case with opacity is transparent, with opacity=0, so we can intval on opacity also
+			$rgba = array_map('intval', $rgba);
 
-            return $rgba;
-        }
+			return $rgba;
+		}
 
-        return null;
-    }
+		return null;
+	}
 
-    /**
-     * Reverse conversion : from RGBA to a color name if possible
-     *
-     * @param integer $r
-     * @param integer $g
-     * @param integer $b
-     * @param integer $a
-     *
-     * @return string|null
-     */
-    public static function RGBaToColorName($r, $g, $b, $a = 1)
-    {
-        static $reverseColorTable = null;
+	/**
+	 * Reverse conversion : from RGBA to a color name if possible
+	 *
+	 * @param integer $r
+	 * @param integer $g
+	 * @param integer $b
+	 * @param integer $a
+	 *
+	 * @return string|null
+	 */
+	public static function RGBaToColorName($r, $g, $b, $a = 1)
+	{
+		static $reverseColorTable = null;
 
-        if (! is_numeric($r) || ! is_numeric($g) || ! is_numeric($b) || ! is_numeric($a)) {
-            return null;
-        }
+		if (! is_numeric($r) || ! is_numeric($g) || ! is_numeric($b) || ! is_numeric($a)) {
+			return null;
+		}
 
-        if ($a < 1) {
-            return null;
-        }
+		if ($a < 1) {
+			return null;
+		}
 
-        if (\is_null($reverseColorTable)) {
-            $reverseColorTable = [];
+		if (\is_null($reverseColorTable)) {
+			$reverseColorTable = [];
 
-            foreach (static::$cssColors as $name => $rgb_str) {
-                $rgb_str = explode(',', $rgb_str);
+			foreach (static::$cssColors as $name => $rgb_str) {
+				$rgb_str = explode(',', $rgb_str);
 
-                if (
-                    \count($rgb_str) == 3 &&
-                    ! isset($reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])])
-                ) {
-                    $reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])] = $name;
-                }
-            }
-        }
+				if (
+					\count($rgb_str) == 3 &&
+					! isset($reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])])
+				) {
+					$reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])] = $name;
+				}
+			}
+		}
 
-        if (isset($reverseColorTable[\intval($r)][\intval($g)][\intval($b)])) {
-            return $reverseColorTable[\intval($r)][\intval($g)][\intval($b)];
-        }
+		if (isset($reverseColorTable[\intval($r)][\intval($g)][\intval($b)])) {
+			return $reverseColorTable[\intval($r)][\intval($g)][\intval($b)];
+		}
 
-        return null;
-    }
+		return null;
+	}
 }

Spacing +2 added lines, -2 removed lines

@@ -213,7 +213,7 @@ 
     {
         static $reverseColorTable = null;
 
-        if (! is_numeric($r) || ! is_numeric($g) || ! is_numeric($b) || ! is_numeric($a)) {
+        if (!is_numeric($r) || !is_numeric($g) || !is_numeric($b) || !is_numeric($a)) {
             return null;
         }
 
@@ -229,7 +229,7 @@ 
 
                 if (
                     \count($rgb_str) == 3 &&
-                    ! isset($reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])])
+                    !isset($reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])])
                 ) {
                     $reverseColorTable[\intval($rgb_str[0])][\intval($rgb_str[1])][\intval($rgb_str[2])] = $name;
                 }