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(PECL ds >= 1.0.0)
Ds\Map::isEmpty — Returns whether the map is empty
此函数没有参数。
示例 #1 Ds\Map::isEmpty() example
<?php
$a = new \Ds\Map(["a" => 1, "b" => 2, "c" => 3]);
$b = new \Ds\Map();
var_dump($a->isEmpty());
var_dump($b->isEmpty());
?>
以上示例的输出类似于:
bool(false) bool(true)