Online PHP editor | refs for HWnS2

<?php class Hoge implements ArrayAccess { public function offsetExists($offset) { var_dump(__METHOD__); return true; } public function offsetGet($offset) { var_dump(__METHOD__); return null; } public function offsetSet($offset, $value) {} public function offsetUnset($offset) {} } $o = new Hoge(); var_dump(empty($o[123])); var_dump(isset($o[123]));