Generic UseCases and UseCaseProvider

[hackolein]

Hello,

is it possible to make the Post Type in the PostUseCase as associatedtype so I write the required method only once:
I started to write the Code, but It dont't work.

Here is the General UseCase in Domain:

public protocol UseCase {
    associatedtype E
    func many() -> Observable<[E]>
    func save(entry: E) -> Observable<Void>
    func delete(entry: E) -> Observable<Void>
}

Here is the General UseCaseProvider in Domain:

public protocol UseCaseProvider {        
    associatedtype U: UseCase
    func makeUseCase() -> U
}

Here is the UserCaseProvider in CoreDataPlatform:

public final class PostUseCaseProvider: Domain.UseCaseProvider {
     private let coreDataStack = CoreDataStack()
    private let postRepository: Repository<Post>

    public init() {
        postRepository = Repository<Post>(context: coreDataStack.context)
    }

    public func makeUseCase() -> Domain.UseCase {
        return PostsUseCase(repository: postRepository)
    }
}

Here get the error Type 'UserCaseProvider' does not conform to protocol 'UseCaseProvider' and Protocol 'UseCase' can only be used as a generic constraint because it has Self or associated type requirements'

Any idea?