I'm not sure I understand the point of this. Or rather, I don't
understand the point of this as distinct from the point of just having
a concept and a template:

```
template<typename C>
concept Container = requires(C c)
{
  {c.begin()} -> is_pointer_type;
  {c.end()} -> is_pointer_type;
  {c.end()} -> std::is_same<decltype(c.begin())>;
  //etc.
};

template<Container C>
auto &operator<<(std::ostream&, C const&c);
```

If there is no vtable, and the lookup is all done at compile-time,
then I see no need to restrict everything to such a coarse mechanism
as overriding specific functions by signature. Concepts are the
compile-time way to define statically-polymorphic prototypes, and
concept-checking is how we declare that a function takes a
statically-polymorphic prototype.

Ok sorry, I was unfamiliar with the latest standards. But my approach is much simpler / cleaner to write for inheritance. What can't we do with inheritance in the first place anyway?

--

Phil Bouchard
Founder
C.: (819) 328-4743