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run code in 300+ PHP versions simultaneously
<?php function arraykey(int|string $arg) : int|string { return $arg; } var_dump([ arraykey("foo") => "foo", arraykey(42) => 42, ]);
Output for 8.1.3 - 8.1.28, 8.2.10 - 8.2.18, 8.3.0 - 8.3.6
array(2) { ["foo"]=> string(3) "foo" [42]=> int(42) }
preferences:
75.08 ms | 402 KiB | 28 Q