Again, thanks for the quick response — had to read that code in github. If I am understanding correctly, I have to use that base_class template to define EVERY relationship between parents and children?
If I have 4 classes in a strict hierarchy Base, D1, D2, D3 (D2 inherits from D1, D3 from D2, etc) do I now have to define the relationship between every possible combination, i.e. <Base, D1>, <Base, D2>, <Base, D3>, <D1, D2> <D1, D3>, <D2, D3> ?
If so that sounds like combinatoric hell as the hierarchy grows.