3v4l.org

run code in 300+ PHP versions simultaneously
<?php declare(strict_types=1); function foo(int $x, int $y = 2, ?int &$z = null) { var_dump(func_num_args()); if ($y != null) { $y = $x ** 2; } return $x * $y; } var_dump([foo(5, $a), $a]); var_dump([foo(3)]);

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24.86 ms | 404 KiB | 5 Q