func parse(JSON: AnyObject?) -> (User?, NSError?) let JSON: AnyObject? = //... let (user, error) = parse(JSON) if let e = error { //... return } if let u = user { //... } else { // maybe user is nil... }
func parse(JSON: AnyObject?) -> Result let JSON: AnyObject? = // ... let result = parse(JSON) switch result { case .Success(let user): // ... case .Failure(let error): // ... }