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run code in 300+ PHP versions simultaneously
<?php class Foo {} $a = null; $f = new Foo($a = 123); var_dump($a); class Bar { function __constructor(){} } $b = null; $g = new Bar($b = 123); var_dump($b); class Baz { function __constructor($x){$x;} } $c = null; $h = new Baz($c = 123); var_dump($c);

preferences:
36.61 ms | 402 KiB | 5 Q