3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $str = 'a\\\\,b,c\\,d'; $str2 = 'a\\\\,b,c\\,d'; var_dump(preg_split('/(?<!(?<!\\\\)\\\\),/', $str)); var_dump(preg_split('/(?<![^\\\\])(?<!\\\\),/', $str2));
based on YFra2
Output for 4.4.5 - 4.4.9, 5.2.0 - 5.6.21, hhvm-3.12.0, 7.0.0 - 7.1.0
array(3) { [0]=> string(3) "a\\" [1]=> string(1) "b" [2]=> string(4) "c\,d" } array(1) { [0]=> string(10) "a\\,b,c\,d" }
Output for hhvm-3.10.0

Process exited with code 153.
Output for 4.3.11 - 4.4.4, 5.0.0 - 5.1.6
array(3) { [0]=> string(3) "a\\" [1]=> string(1) "b" [2]=> string(4) "c\,d" } Warning: preg_split(): Compilation failed: lookbehind assertion is not fixed length at offset 9 in /in/7iHVI on line 5 bool(false)
Output for 4.3.0 - 4.3.10
array(3) { [0]=> string(3) "a\\" [1]=> string(1) "b" [2]=> string(4) "c\,d" } Warning: Compilation failed: lookbehind assertion is not fixed length at offset 9 in /in/7iHVI on line 5 bool(false)