/home/tuzdhajd/tuzdayscloset.com/wp-content/plugins/brizy/vendor/phplrt/grammar/src/Optional.php
<?php
/**
* This file is part of phplrt package.
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
declare(strict_types=1);
namespace Phplrt\Grammar;
use Phplrt\Contracts\Ast\NodeInterface;
use Phplrt\Contracts\Lexer\BufferInterface;
use Phplrt\Contracts\Lexer\TokenInterface;
/**
* Class Optional
*/
class Optional extends Production
{
/**
* @var int|string
*/
public $rule;
/**
* Optional constructor.
*
* @param int|string $rule
*/
public function __construct($rule)
{
$this->rule = $rule;
}
/**
* @return array
*/
public function getConstructorArguments(): array
{
return [$this->rule];
}
/**
* @param BufferInterface $buffer
* @param \Closure $reduce
* @return NodeInterface|TokenInterface|array|null
*/
public function reduce(BufferInterface $buffer, \Closure $reduce)
{
$rollback = $buffer->key();
if (($result = $reduce($this->rule)) !== null) {
return $result;
}
$buffer->seek($rollback);
return [];
}
}