3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php array_keys($categories);
based on Lc5Ec
Output for 5.6.0 - 5.6.30, 7.0.0 - 7.3.0rc3
Notice: Undefined variable: categories in /in/KqYqT on line 3 Warning: array_keys() expects parameter 1 to be array, null given in /in/KqYqT on line 3
Output for hhvm-3.15.4
Notice: Undefined variable: categories in /in/KqYqT on line 3 Warning: array_keys() expects parameter 1 to be an array or collection in /in/KqYqT on line 3