Swift has implicit unwrap (!), and explicit unwrap (?).

I don't like to use implicit unwrap. Even things that are guaranteed to be there, I treat as explicit (For example, (self.view?.isEnabled ?? false), in a view controller, instead of self.view.isEnabled).

I always redefine @IBOutlets from:

    @IBOutlet weak var someView!

    @IBOutlet weak var someView?