Online PHP editor | refs for heZmC

<?php class C implements ArrayAccess { public $data = array( "foo" => null ); public function offsetExists($offset): bool { return array_key_exists((string)$offset, $this->data); } public function offsetGet($offset) { return $this->data[$offset]; } public function offsetSet($offset, $value): void { $this->data[$offset] = $value; } public function offsetUnset($offset): void { unset($this->data[$offset]); } } $o = new C(); var_dump(isset($o['foo'])); var_dump(property_exists($o, 'foo')); var_dump(array_key_exists('foo', $o)); var_dump(array_key_exists('foo', ['foo' => null]));