Extension.swift

/// Private extension
private extension Dependencies {

    /// Resolve a serice based on its ObjectIdentifier
    func resolve<Service>() -> Service {

        var service = self.factories[ObjectIdentifier(Service.self)]!

        guard let instance = service.instance, service.cycle == .global else {

            service.instance = service.createInstance(d: self)
            self.factories[service.name] = service
            return service.instance as! Service

        }

        return instance as! Service
    }

    /// Register a service with our resolver
    private func register(_ service: Service) {
        self.factories[service.name] = service
    }
}