3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $pattern="\( ( (?>[^()]+) | (?R) )* \)"; $str="(def a (x) (+ 1 x))(print (a 1))"; var_dump(preg_match_all ($pattern,$str));
Output for 5.4.0 - 7.1.0
Warning: preg_match_all(): Delimiter must not be alphanumeric or backslash in /in/g3TmF on line 9 bool(false)
Output for 4.3.4 - 5.3.29
Warning: preg_match_all() expects at least 3 parameters, 2 given in /in/g3TmF on line 9 bool(false)
Output for 4.3.3
Warning: Delimiter must not be alphanumeric or backslash in /in/g3TmF on line 9 bool(false)
Output for 4.3.0 - 4.3.2
Warning: Wrong parameter count for preg_match_all() in /in/g3TmF on line 9 NULL