4.swift

/// The PetFamily enum describes the Pet family of objects.
enum PetFamily: String, ClassFamily {
    case cat = "Cat"
    case dog = "Dog"

    static var discriminator: Discriminator = .type

    func getType() -> AnyObject.Type {
        switch self {
        case .cat:
            return Cat.self
        case .dog:
            return Dog.self
        }
    }
}