Visitor.php

<?php

/**
 * Visitor
 *
 * @package Less
 * @subpackage visitor
 */
class Less_Visitor{

	protected $methods = array();
	protected $_visitFnCache = array();

	public function __construct(){
		$this->_visitFnCache = get_class_methods(get_class($this));
		$this->_visitFnCache = array_flip($this->_visitFnCache);
	}

	public function visitObj( $node ){

		$funcName = 'visit'.$node->type;
		if( isset($this->_visitFnCache[$funcName]) ){

			$visitDeeper = true;
			$this->$funcName( $node, $visitDeeper );

			if( $visitDeeper ){
				$node->accept($this);
			}

			$funcName = $funcName . "Out";
			if( isset($this->_visitFnCache[$funcName]) ){
				$this->$funcName( $node );
			}

		}else{
			$node->accept($this);
		}

		return $node;
	}

	public function visitArray( $nodes ){

		array_map( array($this,'visitObj'), $nodes);
		return $nodes;
	}
}