PHP5.5 SplQueue

<?php
// FIFO
$queue = new SplQueue();
echo"Enqueuen";
$queue->enqueue(&#39;A&#39;);
$queue->enqueue(&#39;B&#39;);
$queue->enqueue(&#39;C&#39;);
$queue->push(&#39;D&#39;);
$queue[] = &#39;E&#39;;
foreach($queue as $val) {
echo $val."n";
}
echo"Dequeuen";
$queue->dequeue();
foreach($queue as $val) {
echo $val."n";
}
?>