Multiple Variadic Parameter Pack for Template Class

Question

I am using variadic parameter packs for policy based class design.

template 
class IShader : public Policies... {

};
         


        

Answer 1

Make a nested class, with each layer having one variadic pack. In essence:

template class Wrapper {
public:
    template class Type {
        //Here you have access to both template packs
        //...
    }
}
//Use like this:
Wrapper::Type a;
//...

Define any function of Type outside both classes, but inside the header, or gcc will get confused.

For a more complete use case, see my answer here