3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = "Hello"; $b = function() { echo ",world"; }; $arr = [$a,$b]; array_walk($arr, function($v) { if ($v instanceof Closure) { call_user_func($v); } else { echo $v; } });

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32.19 ms | 402 KiB | 5 Q