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<?php class Baz { protected $foo; protected $bar = null; public function test(){ var_dump(isset($this->foo)); var_dump(isset($this->bar)); return get_object_vars($this); } } var_dump((new Baz)->test());
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
bool(false) bool(false) array(2) { ["foo"]=> NULL ["bar"]=> NULL }

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