3v4l.org

run code in 300+ PHP versions simultaneously
<?php function f($req, $opt = null, $params = null) { printf('$req: %d; $opt: %d; number of params: %d'."\n", $req, $opt, count($params)); var_dump($params); } f(1); f(1, 2); f(1, 2, 3); f(1, 2, 3, 4); f(1, 2, 3, 4, 5); ?>

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38.05 ms | 402 KiB | 5 Q