3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump( preg_split("/a/u", "a\xff"), preg_match("/a/u", "a\xff", $matches), $matches );
Output for 7.3.5 - 7.3.23, 7.4.0 - 7.4.11, 8.0.0alpha1 - rc2
bool(false) bool(false) array(0) { }
Output for 5.3.4 - 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 - 7.3.4
array(1) { [0]=> string(2) "a�" } bool(false) array(0) { }
Output for 4.3.5 - 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 - 5.3.3
array(1) { [0]=> string(2) "a�" } int(0) array(0) { }
Output for 4.3.0 - 4.3.4
array(2) { [0]=> string(0) "" [1]=> string(1) "�" } int(1) array(1) { [0]=> string(1) "a" }