//We can define a namespace as follows:
enum Namespace {
  static let fooConstant: String = "bar"
}

//To use something inside the namespace we just have to write it like this:
let foo: String = Namespace.fooConstant
print(foo) // prints: "bar"

//Now to make use of this is a more usefull environment
enum Request {
  enum Login {
    case with(_ user: User)

    struct User {
      let username: String
      let password: String
    }
  }
}

let user: Request.Login.User = .init(username: "SomeUsername", password: "TheStrongestPasswordEver")
let request: Request.Login = .with(user)