(PECL ds >= 1.0.0)
Ds\Deque::first — Returns the first value in the deque
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The first value in the deque.
UnderflowException if empty.
Example #1 Ds\Deque::first() example
<?php
$deque = new \Ds\Deque([1, 2, 3]);
var_dump($deque->first());
?>
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int(1)