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Re: [v3] constexpr tuple


(removed gcc-patches)

On Thu, 8 Sep 2011, Marc Glisse wrote:

On Thu, 8 Sep 2011, Christopher Jefferson wrote:

This might be totally insane, but I believe that:

tuple_cat(tuple_cat(A,B), C) always equivalent to tuple_cat(A,B,C);

That's a fine way to find the return type, but for code, doesn't it generate many copies? I think I'd forward_as_tuple and use some magic indices to extract everything at once.

Or as an alternative, we could have f<3>(tuple0,tuple1,tuple2) call (with proper forwarding) f<2>(tuple1,tuple2,x01,x02) which calls f<1>(tuple2,x01,x02,x10,x11,x12,x13) which calls f<0>(x01,x02,x10,x11,x12,x13,x20) which is what the tuple constructor needs. This avoids the forward_as_tuple.


--
Marc Glisse


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