3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php echo preg_replace_callback('/([a-z])([A-Z])/', '$1_$2', 'eOaUi'); echo preg_replace_callback('/([a-z])([A-Z])/', function (array $matches) { var_dump($matches); }, 'eOaUi');
Output for 5.3.0 - 7.1.0
Warning: preg_replace_callback(): Requires argument 2, '$1_$2', to be a valid callback in /in/RAVFk on line 3 eOaUiarray(3) { [0]=> string(2) "eO" [1]=> string(1) "e" [2]=> string(1) "O" } array(3) { [0]=> string(2) "aU" [1]=> string(1) "a" [2]=> string(1) "U" } i
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/RAVFk on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/RAVFk on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/RAVFk on line 5
Process exited with code 255.