3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $find = array( "0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f" ); $replace = array( "a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p" ); $find = array_flip($find); echo preg_replace_callback('/[a-f0-9]/', function ($v) use($replace, $find) { return $replace[$find[$v[0]]]; }, $haystack); ?>
Output for 5.3.0 - 5.6.28, hhvm-3.10.0 - 3.13.2, 7.0.0 - 7.1.0
Notice: Undefined variable: haystack in /in/mTNma on line 9
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/mTNma on line 7
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/mTNma on line 7
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/mTNma on line 7
Process exited with code 255.