Re: [boost] [review][mp11] Formal review of Mp11

Joaquin M López Muñoz wrote:

1.7 mp_eval[_xx] functions should accept metafunctions in both their true and false branches.

I can't make this work. #include #include <tuple> template class F, class... T, template class G, class... U> using eval_if = void; int main() { using R = eval_if; } prog.cc:4:55: error: template parameter pack must be the last template parameter template class F, class... T, template class G, class... U> using eval_if = void; ^ One might argue that it ought to work because G would obviously terminate the first pack, but it doesn't. :-) mp_eval_if_c, G, U...> is not pretty but... it works. There's also the option of typename mp_if_c, mp_defer>::type.