3v4l.org

run code in 300+ PHP versions simultaneously
<?php spl_autoload_register('var_dump'); spl_autoload_register(function ($class) { eval('class '.$class.' { }'); }); new Foo(); new \Foo(); use Foo\Bar; new Bar(); use Foo\Baz as Cat; new Cat(); use Foo\Ciz; new Ciz\Caz();

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40.98 ms | 402 KiB | 5 Q