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run code in 300+ PHP versions simultaneously
<?php namespace derp { class Foo {} } namespace herp { class BetterFoo extends \derp\Foo {} class Derp { public function __construct(DerpFoo $foo) {} } class_alias('\derp\Foo', 'DerpFoo'); $f = new Derp(new BetterFoo); }

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31.72 ms | 402 KiB | 5 Q