Ds\Collection::isEmpty

(PECL ds >= 1.0.0)

Ds\Collection::isEmpty — Returns whether the collection is empty

说明

abstract public Ds\Collection::isEmpty ( void ) : bool

Returns whether the collection is empty.

参数

此函数没有参数。

返回值

Returns TRUE if the collection is empty, FALSE otherwise.

范例

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

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

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

以上例程的输出类似于：

bool(false)
bool(true)
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