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                <?php  | 
            
                            
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                namespace GV;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                /** If this file is called directly, abort. */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                if ( ! defined( 'GRAVITYVIEW_DIR' ) )  | 
            
                            
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                	die();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * The base \GV\Shortcode class.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Contains some unitility methods, base class for all GV Shortcodes.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                class Shortcode { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/*  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @var array All GravityView-registered and loaded shortcodes can be found here.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	private static $shortcodes;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @var array The parsed attributes of this shortcode.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	public $atts;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @var string The parsed name of this shortcode.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	public $name;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @var string The parsed content between tags of this shortcode.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	public $content;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * The WordPress Shortcode API callback for this shortcode.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @param array $atts The callback shortcode attributes.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @param string|null $content The wrapped content. Default: null.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @throws \BadMethodCallException in base class.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @return string The result of the shortcode logic.  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
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                	 */  | 
            
            
                                                                        
                            
            
                                    
            
            
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                	public static function callback( $atts, $content = null ) { | 
            
                            
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                		throw new \BadMethodCallException( 'Callback not implemented in base \GV\Shortcode class.' );  | 
            
            
                                                                        
                            
            
                                    
            
            
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                	}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * Register this shortcode class with the WordPress Shortcode API.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @throws \ErrorException if shortcode with this name has already been registered elsewhere.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @internal  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @return \GV\Shortcode The only internally registered instance of this shortcode.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	public static function add() { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		$shortcode = new static();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		if ( shortcode_exists( $shortcode->name ) ) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			if ( empty( self::$shortcodes[$shortcode->name] ) ) { | 
            
                            
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                				throw new \ErrorException( sprintf( 'Shortcode [%s] has already been registered elsewhere.', $shortcode->name ) );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		} else { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			add_shortcode( $shortcode->name, array( get_class( $shortcode ), 'callback' ) );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			self::$shortcodes[$shortcode->name] = $shortcode;  | 
            
                            
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                		}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		return self::$shortcodes[$shortcode->name];  | 
            
                            
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                	}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * Unregister this shortcode.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @internal  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @return void  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	public static function remove() { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		$shortcode = new static();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		unset( self::$shortcodes[$shortcode->name] );  | 
            
                            
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                		remove_shortcode( $shortcode->name );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * Parse a string of content and figure out which ones there are.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * Only registered shortcodes (via add_shortcode) will show up.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * Returned order is not guaranteed.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @param string $content Some post content to search through.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @internal  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 * @return \GV\Shortcode[] An array of \GV\Shortcode (and subclass) instances.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                	public static function parse( $content ) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		$shortcodes = array();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		/**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * The matches contains:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * 1 - An extra [ to allow for escaping shortcodes with double [[]]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * 2 - The shortcode name  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * 3 - The shortcode argument list  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * 4 - The self closing /  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * 5 - The content of a shortcode when it wraps some content.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 * 6 - An extra ] to allow for escaping shortcodes with double [[]]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		preg_match_all( '/' . get_shortcode_regex() . '/', $content, $matches, PREG_SET_ORDER );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                		foreach ( $matches as $shortcode ) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			$shortcode_name = $shortcode[2];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			$shortcode_atts = shortcode_parse_atts( $shortcode[3] );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			$shortcode_content = $shortcode[5];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			/** This is a registered GravityView shortcode. */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			if ( !empty( self::$shortcodes[$shortcode_name] ) ) { | 
            
                            
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                				$shortcode = clone( self::$shortcodes[$shortcode_name] );  | 
            
                            
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                			} else { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                				/** This is some generic shortcode. */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                				$shortcode = new self;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                				$shortcode->name = $shortcode_name;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			$shortcode->atts = $shortcode_atts;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                			$shortcode->content = $shortcode_content;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    127
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    128
                 | 
                                    
                                                     | 
                
                 | 
                			/** Merge inner shortcodes. */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    129
                 | 
                                    
                                                     | 
                
                 | 
                			$shortcodes = array_merge( $shortcodes, array( $shortcode ), self::parse( $shortcode_content ) );  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    130
                 | 
                                    
                                                     | 
                
                 | 
                		}  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    131
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    132
                 | 
                                    
                                                     | 
                
                 | 
                		return $shortcodes;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    133
                 | 
                                    
                                                     | 
                
                 | 
                	}  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
                | 
                    134
                 | 
                                    
                                                     | 
                
                 | 
                }  | 
            
            
                                                        
            
                                    
            
            
                | 
                    135
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                        
The PSR-1: Basic Coding Standard recommends that a file should either introduce new symbols, that is classes, functions, constants or similar, or have side effects. Side effects are anything that executes logic, like for example printing output, changing ini settings or writing to a file.
The idea behind this recommendation is that merely auto-loading a class should not change the state of an application. It also promotes a cleaner style of programming and makes your code less prone to errors, because the logic is not spread out all over the place.
To learn more about the PSR-1, please see the PHP-FIG site on the PSR-1.