(PECL ds >= 1.0.0)
Ds\Map::apply — Updates all values by applying a callback function to each value
Updates all values by applying a callback function to
each value in the map.
callback
A callable to apply to each value in the map.
The callback should return what the value should be replaced by.
没有返回值。
Example #1 Ds\Map::apply() example
<?php
$map = new \Ds\Map(["a" => 1, "b" => 2, "c" => 3]);
$map->apply(function($key, $value) { return $value * 2; });
print_r($map);
?>
以上例程的输出类似于：
Ds\Map Object
(
[0] => Ds\Pair Object
(
[key] => a
[value] => 2
)
[1] => Ds\Pair Object
(
[key] => b
[value] => 4
)
[2] => Ds\Pair Object
(
[key] => c
[value] => 6
)
)