Swift factory helper

Creating.swift

protocol Creating {
    associatedtype Arguments
    associatedtype Service
    func create(_ arguments: Arguments) -> Service
}

extension Creating where Arguments == Void {
    func create() -> Service {
        return create(())
    }
}

class AnyCreating<Arguments, Service>: Creating {

    init<T: Creating>(_ creator: T) where T.Arguments == Arguments, T.Service == Service {
        _create = creator.create
    }

    // MARK: Creating

    func create(_ arguments: Arguments) -> Service {
        return _create(arguments)
    }

    // MARK: Private

    private let _create: (Arguments) -> Service

}