ExtendingInt.swift

protocol Named {
  func GetName() -> String
}

protocol CasedNamed { // previously "NamedExtension"
  func GetLowercaseName() -> String
  func GetUppercaseName() -> String
}

extension CasedName where Self: Named {
  func GetLowercaseName() -> String {
    return self.GetName().lowercaseString
  }
  
  func GetUppercaseName() -> String {
    return self.GetName().uppercaseString
  }
}

extension Int : Named, CasedNamed {
  func GetName() -> String {
    return "Int"
  }
}

1.GetName()          // "Int"
1.GetLowercaseName() // "int"
1.GetUppercaseName() // "INT"