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Ds\Deque::map

PHP function Edit on GitHub ✎

(PECL ds >= 1.0.0)

Returns the result of applying a callback to each value

Description

Ds\Deque::map(callable $callback): Ds\Deque

Returns the result of applying a callback function to each value in the deque.

Parameters

callback
callback(mixed $value): mixed

A callable to apply to each value in the deque.

The callable should return what the new value will be in the new deque.

Return Values

The result of applying a callback to each value in the deque.

Note

The values of the current instance won't be affected.

Examples

Ds\Deque::map() example

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

print_r($deque->map(function($value) { return $value * 2; }));
print_r($deque);
?>

The above example will output something similar to:

output
Ds\Deque Object
(
    [0] => 2
    [1] => 4
    [2] => 6
)
Ds\Deque Object
(
    [0] => 1
    [1] => 2
    [2] => 3
)

Source: reference/ds/ds/deque/map.xml · from the official PHP manual (php/doc-en)