/// <summary>Returns enumerable which when enumerated! resolves all default and named
 /// implementations/registrations of requested service type.
 /// If no services resolved when enumerable accessed, no exception is thrown - enumerable is empty.</summary>
 /// <param name="serviceType">Service type to resolve.</param>
 /// <returns>Returns enumerable which will return resolved service objects.</returns>
 protected override IEnumerable <object> DoGetAllInstances(Type serviceType)
 {
     if (serviceType == null)
     {
         throw new ArgumentNullException(nameof(serviceType));
     }
     return(Container.ResolveAll(serviceType));
 }