Swift result type

Result.swift

enum Result<T, ErrorType> {
  case success(T)
  case error(ErrorType)
}

enum MyError: ErrorType {
  case itFuckedUp 
}

// no longer need unused parameters in completion blocks:
func doSomething(completionHandler: () -> (Result<String, NSError>)) {
  if itWorks {
    completionHandler(.success("it worked"))
  } else {
    completionHandler(.error(.itFuckedUp))
  }
}

doSomething { result in
  switch(result) {
    case .success(let result) {
      
    }
    case .error(let error) {
      
    }
  }
}