Re: [boost] Re: Re: Using MPL on MSVC7

From: Paul Mensonides (pmenso57_at_[hidden])
Date: 2002-12-31 23:21:55

----- Original Message -----
From: "David Abrahams" <dave_at_[hidden]>

> That doesn't do anything to reduce the confusability of the 'typename'
> keyword for me, especially not in Jaap's example:
>
>        template<
>            typename T
>          , typename T::X N
>          >
>        class foo;

No problem.  Scope resolution == not a template type declaration.  Simple.
;)

> > In short, my motivation for using 'typename's here is that I perceive
the
> > 'class' keyword as rather high-weight, semantically loaded, and prefer
to
> > use it in its only original context - that is, for declaring/defining a
> > user-defined type that is more than a POD. Using it in other places
cheapens
> > the word.
>
> As I said (and no offense is intended) these seem to be pedantic
> rather than practical reasons.  I suppose you could say "aesthetic"
> instead of "pedantic", but the practical consequences of those choices
> outweigh the aesthetic ones for me, especially because in a
> metaprogramming context we will commonly use "struct" instead of
> "class"... once again because the practical consequences outweigh the
> aesthetic ones ;-)

And "struct" isn't the half of it.  You can basically lump all
metaprogramming into the category of "not the original intent."  That
includes inheritance, overloading, etc., etc...  Once you start doing heavy
metaprogramming the aesthetic ideal starts to lose its shine.

Paul Mensonides