GetSky\ParserExpressions\Rules\Optional

Complexity

Total Complexity

3

Size/Duplication

Total Lines	45
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	4

Test Coverage

Coverage

100%

Importance

Changes

0

2 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	6	1
A	scan()	0	21	2

<?php
namespace GetSky\ParserExpressions\Rules;

use GetSky\ParserExpressions\Context;
use GetSky\ParserExpressions\Result;
use GetSky\ParserExpressions\RuleInterface;

/**
 * The optional operators consume zero or one consecutive
 * repetitions of their sub-expression e.
 *
 * @package GetSky\ParserExpressions\Rules
 * @author  Alexander Getmanskii <alexander.get87@gmail.com>
 */
class Optional extends AbstractRule
{

    /**
     * @var \GetSky\ParserExpressions\RuleInterface
     */
    protected $rule;

    /**
     * @param array|string|RuleInterface $rule
     * @param string $name
     * @param callable $action
     */
    public function __construct($rule, $name = "Optional", callable $action = null)
    {
        $this->rule = $this->toRule($rule);
        $this->name = (string) $name;
        $this->action = $action;
    }

    /**
     * {@inheritdoc}
     */
    public function scan(Context $context)
    {

        $index = $context->getCursor();

        $context->increaseDepth();
        $value = $this->rule->scan($context);
        $context->decreaseDepth();

        if (is_bool($value)) {
            $context->setCursor($index);
            return true;
        }

        $result = new Result($this->name);
        $result->setValue($value->getValue(), $index);
        $result->addChild($value);
        $this->action($result);

        return $result;
    }
}