Re: [Bug c++/16468] [DR460] using-declaration of namespace name

["Gabriel Dos Reis" <gdr at acm dot org>]

bangerth at dealii dot org:

> As for your question of why a using-declaration should not be allowed to
> name namespace names: using declarations are used to inject declarations
> into a scope, for example into a class scope:

Right.

>   class Base {
>     void f(int);
>   };
>   class Derived : public Base {
>     using Base::f;
>     void f(double);
>   };
> Obviously, allowing a namespace name in a using-declaration inside a class
> declaration does not make much sense.

Why doesn't it make sense?  A definition is a declaration, so
if the namespace has an original-definition, it makes all sense
to bring its name into current scope.

 I think I'm just confused what
> effect
> you try to achieve by allowing namespace names in using-declarations that
> can't be achieved by other means as well?

I'm confused as to why people would like to ban using-declaration
for namespace-names.

-- Gaby