     case invalidSecret(String)
     case invalidAlgorithm(String)
     case invalidDigits(String)
+    case invalidGenerator
 }
 
 private let defaultAlgorithm: Generator.Algorithm = .sha1

        throw DeserializationError.missingSecret
    }
    guard let generator = Generator(factor: factor, secret: secret, algorithm: algorithm, digits: digits) else {
        return nil
    }

    // Skip the leading "/"

}

internal enum DeserializationError: Swift.Error {
    case invalidURLScheme
    case missingFactor
    case invalidFactor(String)
    case invalidCounterValue(String)
