3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php var_dump( @serialize($f), serialize(null), $f != '' );
based on GHATQ
Output for 5.0.4 - 5.0.5, 7.0.0 - 7.1.0
Notice: Undefined variable: f in /in/ERasY on line 6 string(2) "N;" string(2) "N;" bool(false)
Output for 5.1.0 - 5.6.28
Notice: Undefined variable: f in /in/ERasY on line 7 string(2) "N;" string(2) "N;" bool(false)
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: f in /in/ERasY on line 6 string(2) "N;" string(2) "N;" bool(false)