3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php if(preg_match('/Gecko/', $_SERVER['HTTP_USER_AGENT'])) { echo "Damn beast, gecko!"; } else { echo "Damn you!"; }
Output for 5.3.0 - 7.1.10
Notice: Undefined index: HTTP_USER_AGENT in /in/gA4Wt on line 2 Damn you!
Output for 4.3.0 - 5.2.17
Notice: Undefined index: HTTP_USER_AGENT in /in/gA4Wt on line 2 Damn you!