3v4l.org

run code in 500+ PHP versions simultaneously
<?php $a = [1,2,3]; $a[] = &$a; print_r($a); function foo($a) { foreach($a as $b) { if (is_array($b)) { foo($b); } else { print $b.PHP_EOL; } } } // Infinite call //foo($a);

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23.69 ms | 475 KiB | 4 Q