From: Eric Friedman (ebf_at_[hidden])
Date: 2003-11-03 18:21:03
Joel de Guzman wrote:
> Since modern boost libraries with a typelist interface such as tuples
> and variant use MPL anyway, it would be nice to expose a typelist
> typedef so that people can get the typelist and process it using MPL.
I wholeheartedly agree. In fact,
exposes an MPL typesequence containing the logical types of the variant.
Thus, for instance,
variant< int, std::string >::types
, mpl::vector2< int, std::string >
variant< int, recursive_wrapper< X > >::types
, mpl::vector2< int, X >
David Abrahams wrote:
> Ahem. Tuples should already be functioning mpl type sequences, IMO.
> It would be nice if variant would be the same. If not possible in
> either case for some reason, there should be a *non-intrusive*
> type_sequence<X>::type metafunction invocation which gets the type
No offense, but I believe it is a *terrible* idea for any type to have
the dual meanings of 'type sequence' and 'value type'. I've raised this
before; see http://lists.boost.org/MailArchives/boost/msg46807.php.
As always, please feel to tell me if/why I'm wrong.
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