func handle(_ error: Error) {
    switch error {
    // Matching against a group of offline-related errors:
    case URLError.notConnectedToInternet,
         URLError.networkConnectionLost,
         URLError.cannotLoadFromNetwork:
        showOfflineView()
    // Matching against a specific error:
    case let error as HTTPError where error == .unauthorized:
        logOut()
    // Matching against our networking error type:
    case is HTTPError:
        showNetworkErrorView()
    // Fallback for other kinds of errors:
    default:
        showGenericErrorView(for: error)
    }
}