19         $this->withTag = $with_tag;
 
   20         $this->withoutTag = $without_tag;
 
   23     public function validate($string, $config, $context) {
 
   24         $token = $context->get(
'CurrentToken', 
true);
 
   25         if (!$token || $token->name !== $this->tag) {
 
   26             return $this->withoutTag->validate($string, $config, $context);
 
   28             return $this->withTag->validate($string, $config, $context);