3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php var_dump(preg_match("/(?=\xe3\x80\x80)/u", "\xe3\x80\x80")); var_dump(preg_replace("/(?=\xe3\x80\x80)/u", 'xxx', "\xe3\x80\x80"));
Output for 4.3.0 - 5.1.6, 5.2.9 - 7.1.0
int(1) string(6) "xxx "
Output for 5.2.0 - 5.2.8
int(1) NULL