(PECL ds >= 1.0.0)
Ds\Map::ksort — Sorts the map in-place by key
public Ds\Map::ksort ([ callable $comparator ] ) : void
Sorts the map in-place by key, using an optional comparator
function.
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.
callback ( mixed $a, mixed $b ) : int
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.
No value is returned.
Example #1 Ds\Map::ksort() example
<?php $map = new \Ds\Map(["b" => 2, "c" => 3, "a" => 1]); $map->ksort(); print_r($map); ?>
The above example will output something similar to:
Ds\Map Object ( [0] => Ds\Pair Object ( [key] => a [value] => 1 ) [1] => Ds\Pair Object ( [key] => b [value] => 2 ) [2] => Ds\Pair Object ( [key] => c [value] => 3 ) )
Example #2 Ds\Map::ksort() example using a comparator
<?php $map = new \Ds\Map([1 => "x", 2 => "y", 0 => "z"]); // Reverse $map->ksort(function($a, $b) { return $b <=> $a; }); print_r($map); ?>
The above example will output something similar to:
Ds\Map Object Ds\Map Object ( [0] => Ds\Pair Object ( [key] => 2 [value] => y ) [1] => Ds\Pair Object ( [key] => 1 [value] => x ) [2] => Ds\Pair Object ( [key] => 0 [value] => z ) )
© 1997–2020 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/ds-map.ksort.php