diff -r 56308e61381c -r 846026b8422b Twig-1.3.0/lib/Twig/TokenParserBroker.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Twig-1.3.0/lib/Twig/TokenParserBroker.php	Wed Oct 26 21:44:35 2011 +0200
@@ -0,0 +1,107 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2010 Fabien Potencier
+ * (c) 2010 Arnaud Le Blanc
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Default implementation of a token parser broker.
+ *
+ * @package twig
+ * @author  Arnaud Le Blanc <arnaud.lb@gmail.com>
+ */
+class Twig_TokenParserBroker implements Twig_TokenParserBrokerInterface
+{
+    protected $parser;
+    protected $parsers = array();
+    protected $brokers = array();
+
+    /**
+     * Constructor.
+     *
+     * @param array|Traversable $parsers A Traversable of Twig_TokenParserInterface instances
+     * @param array|Traversable $brokers A Traversable of Twig_TokenParserBrokerInterface instances
+     */
+    public function __construct($parsers = array(), $brokers = array())
+    {
+        foreach ($parsers as $parser) {
+            if (!$parser instanceof Twig_TokenParserInterface) {
+                throw new Twig_Error('$parsers must a an array of Twig_TokenParserInterface');
+            }
+            $this->parsers[$parser->getTag()] = $parser;
+        }
+        foreach ($brokers as $broker) {
+            if (!$broker instanceof Twig_TokenParserBrokerInterface) {
+                throw new Twig_Error('$brokers must a an array of Twig_TokenParserBrokerInterface');
+            }
+            $this->brokers[] = $broker;
+        }
+    }
+
+    /**
+     * Adds a TokenParser.
+     *
+     * @param Twig_TokenParserInterface $parser A Twig_TokenParserInterface instance
+     */
+    public function addTokenParser(Twig_TokenParserInterface $parser)
+    {
+        $this->parsers[$parser->getTag()] = $parser;
+    }
+
+    /**
+     * Adds a TokenParserBroker.
+     *
+     * @param Twig_TokenParserBroker $broker A Twig_TokenParserBroker instance
+     */
+    public function addTokenParserBroker(Twig_TokenParserBroker $broker)
+    {
+        $this->brokers[] = $broker;
+    }
+
+    /**
+     * Gets a suitable TokenParser for a tag.
+     *
+     * First looks in parsers, then in brokers.
+     *
+     * @param string $tag A tag name
+     *
+     * @return null|Twig_TokenParserInterface A Twig_TokenParserInterface or null if no suitable TokenParser was found
+     */
+    public function getTokenParser($tag)
+    {
+        if (isset($this->parsers[$tag])) {
+            return $this->parsers[$tag];
+        }
+        $broker = end($this->brokers);
+        while (false !== $broker) {
+            $parser = $broker->getTokenParser($tag);
+            if (null !== $parser) {
+                return $parser;
+            }
+            $broker = prev($this->brokers);
+        }
+        return null;
+    }
+
+    public function getParser()
+    {
+        return $this->parser;
+    }
+
+    public function setParser(Twig_ParserInterface $parser)
+    {
+        $this->parser = $parser;
+        foreach ($this->parsers as $tokenParser) {
+            $tokenParser->setParser($parser);
+        }
+        foreach ($this->brokers as $broker) {
+            $broker->setParser($parser);
+        }
+    }
+}