240 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			240 lines
		
	
	
		
			8.5 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
| <?php
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| 
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| /**
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|  * Injects tokens into the document while parsing for well-formedness.
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|  * This enables "formatter-like" functionality such as auto-paragraphing,
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|  * smiley-ification and linkification to take place.
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|  *
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|  * A note on how handlers create changes; this is done by assigning a new
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|  * value to the $token reference. These values can take a variety of forms and
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|  * are best described HTMLPurifier_Strategy_MakeWellFormed->processToken()
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|  * documentation.
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|  *
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|  * @todo Allow injectors to request a re-run on their output. This
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|  *       would help if an operation is recursive.
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|  */
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| abstract class HTMLPurifier_Injector
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| {
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| 
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|     /**
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|      * Advisory name of injector, this is for friendly error messages
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|      */
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|     public $name;
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| 
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|     /**
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|      * Instance of HTMLPurifier_HTMLDefinition
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|      */
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|     protected $htmlDefinition;
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| 
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|     /**
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|      * Reference to CurrentNesting variable in Context. This is an array
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|      * list of tokens that we are currently "inside"
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|      */
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|     protected $currentNesting;
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| 
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|     /**
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|      * Reference to InputTokens variable in Context. This is an array
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|      * list of the input tokens that are being processed.
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|      */
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|     protected $inputTokens;
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| 
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|     /**
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|      * Reference to InputIndex variable in Context. This is an integer
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|      * array index for $this->inputTokens that indicates what token
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|      * is currently being processed.
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|      */
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|     protected $inputIndex;
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| 
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|     /**
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|      * Array of elements and attributes this injector creates and therefore
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|      * need to be allowed by the definition. Takes form of
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|      * array('element' => array('attr', 'attr2'), 'element2')
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|      */
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|     public $needed = array();
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| 
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|     /**
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|      * Index of inputTokens to rewind to.
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|      */
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|     protected $rewind = false;
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| 
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|     /**
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|      * Rewind to a spot to re-perform processing. This is useful if you
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|      * deleted a node, and now need to see if this change affected any
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|      * earlier nodes. Rewinding does not affect other injectors, and can
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|      * result in infinite loops if not used carefully.
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|      * @warning HTML Purifier will prevent you from fast-forwarding with this
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|      *          function.
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|      */
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|     public function rewind($index) {
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|         $this->rewind = $index;
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|     }
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| 
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|     /**
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|      * Retrieves rewind, and then unsets it.
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|      */
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|     public function getRewind() {
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|         $r = $this->rewind;
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|         $this->rewind = false;
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|         return $r;
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|     }
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| 
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|     /**
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|      * Prepares the injector by giving it the config and context objects:
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|      * this allows references to important variables to be made within
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|      * the injector. This function also checks if the HTML environment
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|      * will work with the Injector (see checkNeeded()).
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|      * @param $config Instance of HTMLPurifier_Config
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|      * @param $context Instance of HTMLPurifier_Context
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|      * @return Boolean false if success, string of missing needed element/attribute if failure
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|      */
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|     public function prepare($config, $context) {
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|         $this->htmlDefinition = $config->getHTMLDefinition();
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|         // Even though this might fail, some unit tests ignore this and
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|         // still test checkNeeded, so be careful. Maybe get rid of that
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|         // dependency.
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|         $result = $this->checkNeeded($config);
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|         if ($result !== false) return $result;
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|         $this->currentNesting =& $context->get('CurrentNesting');
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|         $this->inputTokens    =& $context->get('InputTokens');
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|         $this->inputIndex     =& $context->get('InputIndex');
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|         return false;
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|     }
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| 
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|     /**
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|      * This function checks if the HTML environment
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|      * will work with the Injector: if p tags are not allowed, the
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|      * Auto-Paragraphing injector should not be enabled.
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|      * @param $config Instance of HTMLPurifier_Config
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|      * @param $context Instance of HTMLPurifier_Context
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|      * @return Boolean false if success, string of missing needed element/attribute if failure
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|      */
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|     public function checkNeeded($config) {
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|         $def = $config->getHTMLDefinition();
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|         foreach ($this->needed as $element => $attributes) {
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|             if (is_int($element)) $element = $attributes;
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|             if (!isset($def->info[$element])) return $element;
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|             if (!is_array($attributes)) continue;
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|             foreach ($attributes as $name) {
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|                 if (!isset($def->info[$element]->attr[$name])) return "$element.$name";
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|             }
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|         }
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|         return false;
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|     }
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| 
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|     /**
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|      * Tests if the context node allows a certain element
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|      * @param $name Name of element to test for
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|      * @return True if element is allowed, false if it is not
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|      */
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|     public function allowsElement($name) {
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|         if (!empty($this->currentNesting)) {
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|             $parent_token = array_pop($this->currentNesting);
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|             $this->currentNesting[] = $parent_token;
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|             $parent = $this->htmlDefinition->info[$parent_token->name];
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|         } else {
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|             $parent = $this->htmlDefinition->info_parent_def;
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|         }
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|         if (!isset($parent->child->elements[$name]) || isset($parent->excludes[$name])) {
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|             return false;
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|         }
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|         // check for exclusion
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|         for ($i = count($this->currentNesting) - 2; $i >= 0; $i--) {
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|             $node = $this->currentNesting[$i];
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|             $def  = $this->htmlDefinition->info[$node->name];
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|             if (isset($def->excludes[$name])) return false;
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|         }
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|         return true;
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|     }
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| 
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|     /**
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|      * Iterator function, which starts with the next token and continues until
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|      * you reach the end of the input tokens.
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|      * @warning Please prevent previous references from interfering with this
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|      *          functions by setting $i = null beforehand!
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|      * @param &$i Current integer index variable for inputTokens
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|      * @param &$current Current token variable. Do NOT use $token, as that variable is also a reference
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|      */
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|     protected function forward(&$i, &$current) {
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|         if ($i === null) $i = $this->inputIndex + 1;
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|         else $i++;
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|         if (!isset($this->inputTokens[$i])) return false;
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|         $current = $this->inputTokens[$i];
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|         return true;
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|     }
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| 
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|     /**
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|      * Similar to _forward, but accepts a third parameter $nesting (which
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|      * should be initialized at 0) and stops when we hit the end tag
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|      * for the node $this->inputIndex starts in.
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|      */
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|     protected function forwardUntilEndToken(&$i, &$current, &$nesting) {
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|         $result = $this->forward($i, $current);
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|         if (!$result) return false;
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|         if ($nesting === null) $nesting = 0;
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|         if     ($current instanceof HTMLPurifier_Token_Start) $nesting++;
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|         elseif ($current instanceof HTMLPurifier_Token_End) {
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|             if ($nesting <= 0) return false;
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|             $nesting--;
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|         }
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|         return true;
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|     }
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| 
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|     /**
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|      * Iterator function, starts with the previous token and continues until
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|      * you reach the beginning of input tokens.
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|      * @warning Please prevent previous references from interfering with this
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|      *          functions by setting $i = null beforehand!
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|      * @param &$i Current integer index variable for inputTokens
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|      * @param &$current Current token variable. Do NOT use $token, as that variable is also a reference
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|      */
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|     protected function backward(&$i, &$current) {
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|         if ($i === null) $i = $this->inputIndex - 1;
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|         else $i--;
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|         if ($i < 0) return false;
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|         $current = $this->inputTokens[$i];
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|         return true;
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|     }
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| 
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|     /**
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|      * Initializes the iterator at the current position. Use in a do {} while;
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|      * loop to force the _forward and _backward functions to start at the
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|      * current location.
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|      * @warning Please prevent previous references from interfering with this
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|      *          functions by setting $i = null beforehand!
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|      * @param &$i Current integer index variable for inputTokens
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|      * @param &$current Current token variable. Do NOT use $token, as that variable is also a reference
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|      */
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|     protected function current(&$i, &$current) {
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|         if ($i === null) $i = $this->inputIndex;
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|         $current = $this->inputTokens[$i];
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|     }
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| 
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|     /**
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|      * Handler that is called when a text token is processed
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|      */
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|     public function handleText(&$token) {}
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| 
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|     /**
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|      * Handler that is called when a start or empty token is processed
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|      */
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|     public function handleElement(&$token) {}
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| 
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|     /**
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|      * Handler that is called when an end token is processed
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|      */
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|     public function handleEnd(&$token) {
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|         $this->notifyEnd($token);
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|     }
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| 
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|     /**
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|      * Notifier that is called when an end token is processed
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|      * @note This differs from handlers in that the token is read-only
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|      * @deprecated
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|      */
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|     public function notifyEnd($token) {}
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| 
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| 
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| }
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| 
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| // vim: et sw=4 sts=4
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