Re: A couple of issues in submitting typelists to boost

From: Gennadiy E. Rozental (rogeeff_at_[hidden])
Date: 2001-11-19 20:06:52

--- In boost_at_y..., "Andrei Alexandrescu" <andrewalex_at_h...> wrote:
> Thanks for all the info. Quick answer below.
> 
> > Maybe you'd better explain SUPERSUBCLASS to those of us that 
don't know.
> 
> ////////////////////////////////////////////////////////////////////
////////
> ////
> // macro SUPERSUBCLASS
> // Invocation: SUPERSUBCLASS(B, D) where B and D are types.
> // Returns true if B is a public base of D, or if B and D are 
aliases of the
> // same type.
> //
> // Caveat: might not work if T and U are in a private inheritance 
hierarchy.
> ////////////////////////////////////////////////////////////////////
////////
> ////
> 
> #define SUPERSUBCLASS(T, U) \
>     (::Loki::Conversion<const U*, const T*>::exists && \
>     !::Loki::Conversion<const T*, const void*>::sameType)
> 

Why don't to implement this using boost::is_convertable and 
boost::same_type?

Gennadiy.

> Now I also notice there's a bug: I should qualify the types with 
volatile as
> well. Volatile hits again :o).
> 
> Cheers,
> 
> Andrei