3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $array = array(0 => 100, "color" => "red"); print_r(array_keys($array));
Output for 4.3.0 - 5.6.30, hhvm-3.10.1 - 3.21.0, 7.0.0 - 7.0.19, 7.1.0 - 7.1.8
Array ( [0] => 0 [1] => color )
Output for 7.0.20

Process exited with code 137.