How to dispatch a class function for an object accessed by handle?

[Adam D. Ruppe]

On Friday, 6 March 2020 at 14:05:55 UTC, Steven Schveighoffer 
wrote:
> Adam's way doesn't work either, because the call doesn't use 
> the alias, but just instantiates opDispatch with the new name!'

oh yikes, how did I not notice that?!

so yeah just kinda screwed. I'd probably suggest at tis point 
having the opDispatch be a trivial implementation that just 
forwards to another named method.

struct A {
   template opDispatch(string name) {
      auto opDispatch(T, Args...)(Args args) {
            return other_name!(name, T, Args)(args);
      }
   }

   auto other_name(string name, T, Args...)(Args args) {
       // real implementation
   }
}


and then to test it externally you do

a.other_name!("whatever", Bitmap)(args, here);