inc/Twig/Node/Expression/Test/Defined.php

   1 <?php
   2
   3 /*
   4  * This file is part of Twig.
   5  *
   6  * (c) 2011 Fabien Potencier
   7  *
   8  * For the full copyright and license information, please view the LICENSE
   9  * file that was distributed with this source code.
  10  */
  11
  12 /**
  13  * Checks if a variable is defined in the current context.
  14  *
  15  * <pre>
  16  * {# defined works with variable names and variable attributes #}
  17  * {% if foo is defined %}
  18  *     {# ... #}
  19  * {% endif %}
  20  * </pre>
  21  *
  22  * @author Fabien Potencier <fabien@symfony.com>
  23  */
  24 class Twig_Node_Expression_Test_Defined extends Twig_Node_Expression_Test
  25 {
  26     public function __construct(Twig_NodeInterface $node, $name, Twig_NodeInterface $arguments = null, $lineno)
  27     {
  28         parent::__construct($node, $name, $arguments, $lineno);
  29
  30         if ($node instanceof Twig_Node_Expression_Name) {
  31             $node->setAttribute('is_defined_test', true);
  32         } elseif ($node instanceof Twig_Node_Expression_GetAttr) {
  33             $node->setAttribute('is_defined_test', true);
  34
  35             $this->changeIgnoreStrictCheck($node);
  36         } else {
  37             throw new Twig_Error_Syntax('The "defined" test only works with simple variables', $this->getLine());
  38         }
  39     }
  40
  41     protected function changeIgnoreStrictCheck(Twig_Node_Expression_GetAttr $node)
  42     {
  43         $node->setAttribute('ignore_strict_check', true);
  44
  45         if ($node->getNode('node') instanceof Twig_Node_Expression_GetAttr) {
  46             $this->changeIgnoreStrictCheck($node->getNode('node'));
  47         }
  48     }
  49
  50     public function compile(Twig_Compiler $compiler)
  51     {
  52         $compiler->subcompile($this->getNode('node'));
  53     }
  54 }