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diff --git a/ext/spl/internal/splqueue.inc b/ext/spl/internal/splqueue.inc
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+<?php
+
+/** @file splqueue.inc
+ * @ingroup SPL
+ * @brief class SplQueue
+ * @author  Etienne Kneuss
+ * @date    2008 - 2009
+ *
+ * SPL - Standard PHP Library
+ */
+
+/** @ingroup SPL
+ * @brief Implementation of a Queue through a DoublyLinkedList. As SplQueue
+ *        extends SplDoublyLinkedList, unshift() and pop() are still available 
+ *        even though they don't make much sense for a queue. For convenience,
+ *        two aliases are available:
+ *         - enqueue() is an alias of push()
+ *         - dequeue() is an alias of shift()
+ *
+ * @since PHP 5.3
+ *
+ * The SplQueue class provides the main functionalities of a
+ * queue implemented using a doubly linked list (DLL).
+ */
+class SplQueue extends SplDoublyLinkedList
+{
+	protected $_it_mode = parent::IT_MODE_FIFO;
+
+	/** Changes the iteration mode. There are two orthogonal sets of modes that 
+	 * can be set:
+	 *
+	 * - The behavior of the iterator (either one or the other)
+	 *  - SplDoublyLnkedList::IT_MODE_DELETE (Elements are deleted by the iterator)
+	 *  - SplDoublyLnkedList::IT_MODE_KEEP   (Elements are traversed by the iterator)
+	 *
+	 * The default mode is 0 : SplDoublyLnkedList::IT_MODE_LIFO | SplDoublyLnkedList::IT_MODE_KEEP
+	 *
+	 * @note The iteration's direction is not modifiable for queue instances
+	 * @param $mode              New mode of iteration
+	 * @throw RuntimeException   If the new mode affects the iteration's direction.
+	 */
+	public function setIteratorMode($mode)
+	{
+		if ($mode & parent::IT_MODE_LIFO === parent::IT_MODE_LIFO) {
+			throw new RuntimeException("Iterators' LIFO/FIFO modes for SplStack/SplQueue objects are frozen");
+		}
+
+		$this->_it_mode = $mode;
+	}
+
+	/** @return the first element of the queue.
+	 * @note dequeue is an alias of push()
+	 * @see splDoublyLinkedList::push()
+	 */
+	public function dequeue()
+	{
+		return parent::shift();
+	}
+
+	/** Pushes an element at the end of the queue.
+	 * @param $data variable to add to the queue.
+	 * @note enqueue is an alias of shift()
+	 * @see splDoublyLinkedList::shift()
+	 */
+	public function enqueue($data)
+	{
+		return parent::push($data);
+	}
+}
+
+?>