3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $string = '--'; $doesNotMatchInPhp7 = '/(?|(---)|(-))\1/'; $matchesInPhp7 = '/(?|(-)|(---))\1/'; var_dump(preg_match($doesNotMatchInPhp7, $string)); var_dump(preg_match($matchesInPhp7, $string));
based on jLqhL
Output for hhvm-3.15.4, 7.0.0 - 7.2.6
int(0) int(1)
Output for 5.6.0 - 5.6.30
int(1) int(1)