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protocol ViewModelBased: class {
    associatedtype ViewModelType: ViewModel
    var viewModel: ViewModelType { get set }
}

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extension ViewModelBased where Self: StoryboardBased & UIViewController {
    static func instantiate<ServicesT> (withServices services: ServicesT) -> Self
    where ServicesT == Self.ViewModelType.Services {
        let viewController = Self.instantiate()
        viewController.viewModel = ViewModelType(withServices: services)
        return viewController
    }
}

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class MyService {
    func executeService() {
        print ("Service execution")
    }
}

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struct MyViewModel: ViewModel {
    typealias Services = MyService
    init(withServices services: Services) {
        services.executeService()
    }
}

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let myViewController = MyViewController.instantiate(withServices: myService)
// we can access the inner ViewModel if needed: myViewController.viewModel

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class Service1 {
    func executeService1() {
        print ("execution of Service1")
    }
}

class Service2 {
    func executeService2() {
        print ("execution of Service2")
    }

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protocol HasService1 {
    var service1: Service1 { get }
}

protocol HasService2 {
    var service2: Service2 { get }
}

protocol HasService3 {
    var service3: Service3 { get }

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struct MyViewModel: ViewModel {
    // thanks to protocol composition we define only the services we want to use
    typealias Services = HasService1 & HasService2
    init(withServices services: Services) {
        services.service1.executeService1()
        services.service2.executeService2()
    }
}

struct MyOtherViewModel: ViewModel {

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class MyServices: HasService1, HasService2, HasService3 {
    let service1 = Service1()
    let service2 = Service2()
    let service3 = Service3()
}

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let myViewController = MyViewController.instantiate(withServices: myServices)
let myViewController2 = MyViewController2.instantiate(withServices: myServices)
// This is the same myServices instance for the 2 ViewControllers
// but each ViewModel will only access what's needed