3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $str = 'a\\\\,b,c\\,d'; var_dump(preg_split('/(?<!(?=[^\\\]).[\\\]),/', $str));
based on EMFOC
Output for 4.3.0 - 5.6.25, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
array(3) { [0]=> string(3) "a\\" [1]=> string(1) "b" [2]=> string(4) "c\,d" }