3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $array = array( 1, null, 3 ); $keys = array_keys($array); print_r($keys);
based on 6JpBr
Output for 4.3.0 - 7.2.0
Array ( [0] => 0 [1] => 1 [2] => 2 )