Map
PHP Manual

Ds\Map::keys

(PECL ds >= 1.0.0)

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

Description

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

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"
}

Map
PHP Manual