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Ds\Queue::peek

(PECL ds >= 1.0.0)

Ds\Queue::peek — Returns the value at the front of the queue

Descrizione

public Ds\Queue::peek(): mixed

Returns the value at the front of the queue, but does not remove it.

Elenco dei parametri

Questa funzione non contiene parametri.

Valori restituiti

The value at the front of the queue.

Errori/Eccezioni

UnderflowException if empty.

Esempi

Example #1 Ds\Queue::peek() example

<?php
$queue = new \Ds\Queue();

$queue->push("a");
$queue->push("b");
$queue->push("c");

var_dump($queue->peek());
?>

Il precedente esempio visualizzerà qualcosa simile a:

string(1) "a"