3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $str = "https://www.youtube.com/watch?v=kS4e4ozg0HU"; echo preg_match('/^https://www.youtube.com/watch?v=(.*)/', $str);
Output for 4.3.11 - 7.1.0
Warning: preg_match(): Unknown modifier '/' in /in/D31oM on line 4
Output for 4.3.0 - 4.3.10
Warning: Unknown modifier '/' in /in/D31oM on line 4