On 10/20/09 05:18, luozhiyuan wrote:

Is it possible that BOOST_MPL_LIMIT_/seq/_SIZE can be removed when we have variadic templates ?

Yes. Please see: http://article.gmane.org/gmane.comp.lib.boost.devel/194084 The compiler patch mentioned there how been applied: http://gcc.gnu.org/ml/gcc-patches/2009-10/msg00892.html One thing missing is a variadic version of arg<I>. What's needed for that is some way to index the pack expansion. IOW, template<int Idx> struct arg { template<typename... Args> apply { typedef Args...[Idx] type; }; }; where Args...[Idx] returns the Idx-th type in the pack expansion, Args.... Apparently there's some problem about how that can be expressed unambiguously. Search for "most-requested" here: http://groups.google.com/group/comp.std.c++/msg/40705c1e2a6f78f8 -regards, Larry