I'm curious, would C++ ever consider categories like in ObjC? I.e. class extensions that unlike inheritance don't change the type. It kind of gets close with t

I'm curious, would C++ ever consider categories like in ObjC? I.e. class extensions that unlike inheritance don't change the type. It kind of gets close with the unified call: if you have a call f(x,y) then either x.f(y) is matched or some f(x,y) that may be defined elsewhere. But still not the same as the ability to define a new x.g(y) for an existing class. (Edit: I can't even start to think what implications this will have on templates. They will probably become even more impenetrable.)