3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php strtoupper ( $string1 ); ?>
based on gjMl6
Output for 5.0.4 - 7.2.0
Notice: Undefined variable: string1 in /in/d4A6M on line 2
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: string1 in /in/d4A6M on line 2