class ServiceCreator<T> {}

interface I
{
  void Publish<T>(T serviceInstance) where T : class;
  void Publish<T>(ServiceCreator<T> serviceCreator) where T : class;  
}

interface ISampleService {}

class C
{
  public void Foo (I i)
  {
    i.Publish<ISampleService> (null);
  }
}