Ds\Map::sort

Sorts the map in-place by value

Description

public void Ds\Map::sort(callable $comparator = ?)

Sorts the map in-place by value, using an optional comparator function.

Parameters

comparator

The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.

int callback(mixed $a, mixed $b)
Caution

Returning non-integer values from the comparison function, such as float, will result in an internal cast to int of the callback's return value. So values such as 0.99 and 0.1 will both be cast to an integer value of 0, which will compare such values as equal.

Return Values

No value is returned.

Examples

Example #1 Ds\Map::sort example

<?php
$map = new \Ds\Map(["a" => 2, "b" => 3, "c" => 1]);
$map->sort();

print_r($map);
?>

The above example will output something similar to:

Ds\Map Object
(
    [0] => Ds\Pair Object
        (
            [key] => c
            [value] => 1
        )

    [1] => Ds\Pair Object
        (
            [key] => a
            [value] => 2
        )

    [2] => Ds\Pair Object
        (
            [key] => b
            [value] => 3
        )

)

Example #2 Ds\Map::sort example using a comparator

<?php
$map = new \Ds\Map(["a" => 2, "b" => 3, "c" => 1]);

$map->sort(function($a, $b) {
    return $b <=> $a;
});

print_r($map);
?>

The above example will output something similar to:

Ds\Map Object
(
    [0] => Ds\Pair Object
        (
            [key] => b
            [value] => 3
        )

    [1] => Ds\Pair Object
        (
            [key] => a
            [value] => 2
        )

    [2] => Ds\Pair Object
        (
            [key] => c
            [value] => 1
        )

)