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Ds\Queue::isEmpty

(PECL ds >= 1.0.0)

Ds\Queue::isEmpty — Returns whether the queue is empty

说明

public Ds\Queue::isEmpty(): bool

Returns whether the queue is empty.

参数

此函数没有参数。

返回值

Returns true if the queue is empty, false otherwise.

示例

示例 #1 Ds\Queue::isEmpty() example

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

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

以上示例的输出类似于：

bool(false)
bool(true)