Returns a set of the map's keys.
Returns a set containing all the keys of the map, in the same order.
This function has no parameters.
A Ds\Set containing all the keys of the map.
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" }