106 lines
2.4 KiB
PHP
106 lines
2.4 KiB
PHP
<?php
|
|
|
|
/*
|
|
* This file is part of the Symfony package.
|
|
*
|
|
* (c) Fabien Potencier <fabien@symfony.com>
|
|
*
|
|
* For the full copyright and license information, please view the LICENSE
|
|
* file that was distributed with this source code.
|
|
*/
|
|
|
|
namespace Symfony\Component\CssSelector;
|
|
|
|
/**
|
|
* TokenStream represents a stream of CSS Selector tokens.
|
|
*
|
|
* This component is a port of the Python lxml library,
|
|
* which is copyright Infrae and distributed under the BSD license.
|
|
*
|
|
* @author Fabien Potencier <fabien@symfony.com>
|
|
*/
|
|
class TokenStream
|
|
{
|
|
private $used;
|
|
private $tokens;
|
|
private $source;
|
|
private $peeked;
|
|
private $peeking;
|
|
|
|
/**
|
|
* Constructor.
|
|
*
|
|
* @param array $tokens The tokens that make the stream.
|
|
* @param mixed $source The source of the stream.
|
|
*/
|
|
public function __construct($tokens, $source = null)
|
|
{
|
|
$this->used = array();
|
|
$this->tokens = $tokens;
|
|
$this->source = $source;
|
|
$this->peeked = null;
|
|
$this->peeking = false;
|
|
}
|
|
|
|
/**
|
|
* Gets the tokens that have already been visited in this stream.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function getUsed()
|
|
{
|
|
return $this->used;
|
|
}
|
|
|
|
/**
|
|
* Gets the next token in the stream or null if there is none.
|
|
* Note that if this stream was set to be peeking its behavior
|
|
* will be restored to not peeking after this operation.
|
|
*
|
|
* @return mixed
|
|
*/
|
|
public function next()
|
|
{
|
|
if ($this->peeking) {
|
|
$this->peeking = false;
|
|
$this->used[] = $this->peeked;
|
|
|
|
return $this->peeked;
|
|
}
|
|
|
|
if (!count($this->tokens)) {
|
|
return null;
|
|
}
|
|
|
|
$next = array_shift($this->tokens);
|
|
$this->used[] = $next;
|
|
|
|
return $next;
|
|
}
|
|
|
|
/**
|
|
* Peeks for the next token in this stream. This means that the next token
|
|
* will be returned but it won't be considered as used (visited) until the
|
|
* next() method is invoked.
|
|
* If there are no remaining tokens null will be returned.
|
|
*
|
|
* @see next()
|
|
*
|
|
* @return mixed
|
|
*/
|
|
public function peek()
|
|
{
|
|
if (!$this->peeking) {
|
|
if (!count($this->tokens)) {
|
|
return null;
|
|
}
|
|
|
|
$this->peeked = array_shift($this->tokens);
|
|
|
|
$this->peeking = true;
|
|
}
|
|
|
|
return $this->peeked;
|
|
}
|
|
}
|