3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php function x($a){ return (string)$a; } echo x($b);
based on mCbQ6
Output for 5.0.4 - 7.3.0rc4
Notice: Undefined variable: b in /in/SLMQS on line 5
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: b in /in/SLMQS on line 5