BaseNodeVisitor.php (1856B)
1 <?php 2 3 /* 4 * This file is part of Twig. 5 * 6 * (c) 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 * Twig_BaseNodeVisitor can be used to make node visitors compatible with Twig 1.x and 2.x. 14 * 15 * @author Fabien Potencier <fabien@symfony.com> 16 */ 17 abstract class Twig_BaseNodeVisitor implements Twig_NodeVisitorInterface 18 { 19 /** 20 * {@inheritdoc} 21 */ 22 final public function enterNode(Twig_NodeInterface $node, Twig_Environment $env) 23 { 24 if (!$node instanceof Twig_Node) { 25 throw new LogicException('Twig_BaseNodeVisitor only supports Twig_Node instances.'); 26 } 27 28 return $this->doEnterNode($node, $env); 29 } 30 31 /** 32 * {@inheritdoc} 33 */ 34 final public function leaveNode(Twig_NodeInterface $node, Twig_Environment $env) 35 { 36 if (!$node instanceof Twig_Node) { 37 throw new LogicException('Twig_BaseNodeVisitor only supports Twig_Node instances.'); 38 } 39 40 return $this->doLeaveNode($node, $env); 41 } 42 43 /** 44 * Called before child nodes are visited. 45 * 46 * @param Twig_Node $node The node to visit 47 * @param Twig_Environment $env The Twig environment instance 48 * 49 * @return Twig_Node The modified node 50 */ 51 abstract protected function doEnterNode(Twig_Node $node, Twig_Environment $env); 52 53 /** 54 * Called after child nodes are visited. 55 * 56 * @param Twig_Node $node The node to visit 57 * @param Twig_Environment $env The Twig environment instance 58 * 59 * @return Twig_Node|false The modified node or false if the node must be removed 60 */ 61 abstract protected function doLeaveNode(Twig_Node $node, Twig_Environment $env); 62 }