3v4l.org

run code in 300+ PHP versions simultaneously
<?php $str = 'a,b\\\,c,d'; var_dump(preg_split('/(?<!(?!\x5c)(?=\x5c)),/', $str));
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(4) { [0]=> string(1) "a" [1]=> string(3) "b\\" [2]=> string(1) "c" [3]=> string(1) "d" }

preferences:
292.54 ms | 405 KiB | 455 Q