[cfe-dev] Error on valid; and q. about using tentative parse

[Robinson, Paul]

From: Dmitri Gribenko [mailto:gribozavr at gmail.com]
> On Wed, Feb 6, 2013 at 10:24 PM, Robinson, Paul
> <Paul.Robinson at am.sony.com> wrote:
> > Clang is giving a compile time error on the following test case:
> >
> >     template<int V0>
> >     struct T0
> >     {
> >         enum { E = V0 };
> >     };
> >
> >     template<int V1>
> >     struct T1
> >     {
> >         // The name declared here is the same as the type template
> >         // declared above.
> >         static int const T0 = T0<V1>::E;
> >     };
> >
> > with the compile time error:
> >
> >     test.cpp:12:35: error: no member named 'E' in the global namespace
> >       static int const T0 = T0<V1>::E;
> 
> I believe this is correct, the code is parsed as (T0 less-than V1)
> greater-than ::E.
> 
> ::T0<V1>::E would do what you want.
> 
> Dmitri

Okay, I see that the point-of-declaration of the int T0 is prior to the
initializer, so unqualified lookup of the T0 from T0<V1>::E will find
the int T0.  I guess I was confused by the similar-seeming case where 
struct T0 is not a template, and if we see
  static int const T0 = T0::E;
then the T0::E is resolved as a qualified reference to member E of
struct T0.  But delving deeper into the standard, I guess T0<V1> doesn't
count as a nested-name-specifier, so I do need the leading :: to get the
effect I want.

Thanks,
--paulr