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run code in 300+ PHP versions simultaneously
<?php $a = 'foo'; $b = 'bar'; $array = [&$a, $b]; var_dump($array); array_map(function($item){ if ($item == 'foo') { echo 'yep!!'; return 'fizz'; } }, $array); var_dump($array);

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41.09 ms | 402 KiB | 5 Q