Overview
KB
Technical FAQ
PHP Manual
CSS2 Manual
HTML Manual
JS Guide
JS Reference
PhpDock Manual
Nu-Coder Manual
PhpExpress Manual
PHP Joomla
Development
Learn PHP
 
<Ds\Deque::insertDs\Deque::join>
^Ds\DequeLast updated: Mon, 26 Oct 2026

Ds\Deque::isEmpty

(PECL ds >= 1.0.0)

Ds\Deque::isEmpty — Returns whether the deque is empty

Description

public function Ds\Deque::isEmpty(): bool

Returns whether the deque is empty.

Parameters

This function has no parameters.

Return Values

Returns true if the deque is empty, false otherwise.

Examples

Example #1 Ds\Deque::isEmpty() example

<?php
$a = new \Ds\Deque([1, 2, 3]);
$b = new \Ds\Deque();

var_dump($a->isEmpty());
var_dump($b->isEmpty());
?>

The above example will output something similar to:

bool(false)
bool(true)

<Ds\Deque::insertDs\Deque::join>
^Ds\DequeLast updated: Mon, 26 Oct 2026