self.rx.viewDidLoad
  .subscribe(onNext: {
    print("viewDidLoad 🎉")
  })

extension Reactive where Base: UIViewController {
  var viewDidLoad: ControlEvent<Void>

  var viewWillAppear: ControlEvent<Bool>
  var viewDidAppear: ControlEvent<Bool>

  var viewWillDisappear: ControlEvent<Bool>
  var viewDidDisappear: ControlEvent<Bool>

  var viewWillLayoutSubviews: ControlEvent<Void>
  var viewDidLayoutSubviews: ControlEvent<Void>

  var willMoveToParentViewController: ControlEvent<UIViewController?>
  var didMoveToParentViewController: ControlEvent<UIViewController?>

  var didReceiveMemoryWarning: ControlEvent<Void>
}

public extension Reactive where Base: NSViewController {
  var viewDidLoad: ControlEvent<Void>

  var viewWillAppear: ControlEvent<Void>
  var viewDidAppear: ControlEvent<Void>

  var viewWillDisappear: ControlEvent<Void>
  var viewDidDisappear: ControlEvent<Void>

  var viewWillLayout: ControlEvent<Void>
  var viewDidLayout: ControlEvent<Void>
}