(PECL ds >= 1.0.0)
Ds\Queue::peek — Returns the value at the front of the queue
Returns the value at the front of the queue, but does not remove it.
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The value at the front of the queue.
UnderflowException if empty.
Example #1 Ds\Queue::peek() example
<?php
$queue = new \Ds\Queue();
$queue->push("a");
$queue->push("b");
$queue->push("c");
var_dump($queue->peek());
?>
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string(1) "a"