import Foundation

// Removing the subclassing from NSObject fixes the problem
class Animal: NSObject {
}

protocol Named {
    init(name: String)
}

protocol AnimalSpecification {
    associatedtype AnimalType: Animal
}

extension AnimalSpecification where AnimalType: Named {
    func animal(named name: String) -> AnimalType {
        return AnimalType(name: name)
    }
}

class Dog: Animal, Named {
    let name: String
    required init(name: String) {
        self.name = name
        super.init()
    }
}

struct Kennel: AnimalSpecification {
    typealias AnimalType = Dog
}

let kennel = Kennel()
kennel.animal(named: "Brian")