3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $subject = 'все кроме ямайка'; $result = preg_replace('/(\s)?ямайка(?(1)|\s?)/x', '', $subject); echo $result;
based on tWBi3
Output for 4.3.0 - 5.6.28, hhvm-3.12.0, 7.0.0 - 7.1.0
все кроме
Output for hhvm-3.10.0

Process exited with code 153.