Online PHP editor | vld for bvYi0

<?php $x = new __PHP_Incomplete_Class(); var_dump(is_object($x)); class Foo extends __PHP_Incomplete_Class { } $y = new Foo(); var_dump(is_object($y)); class Bar extends stdClass { } $z = new Bar(); var_dump(is_object($z)); var_dump($x instanceof stdClass); var_dump($y instanceof stdClass); var_dump($z instanceof stdClass);