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<Ds\Map::jsonSerializeDs\Map::ksort>
^Ds\MapLast updated: Mon, 26 Oct 2026

Ds\Map::keys

(PECL ds >= 1.0.0)

Ds\Map::keys — Returns a set of the map's keys

Description

public function Ds\Map::keys(): Ds\Set

Returns a set containing all the keys of the map, in the same order.

Parameters

This function has no parameters.

Return Values

A Ds\Set containing all the keys of the map.

Examples

Example #1 Ds\Map::keys() example

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

The above example will output something similar to:

object(Ds\Set)#2 (3) {
  [0]=>
  string(1) "a"
  [1]=>
  string(1) "b"
  [2]=>
  string(1) "c"
}

<Ds\Map::jsonSerializeDs\Map::ksort>
^Ds\MapLast updated: Mon, 26 Oct 2026