How do I expand a tuple into variadic template function's arguments?

Question

Consider the case of a templated function with variadic template arguments:

template Tret func(const T&... t);
         


        

Answer 1

The news does not look good.

Having read over the just-released draft standard, I'm not seeing a built-in solution to this, which does seem odd.

The best place to ask about such things (if you haven't already) is comp.lang.c++.moderated, because some folks involved in drafting the standard post there regularly.

If you check out this thread, someone has the same question (maybe it's you, in which case you're going to find this whole answer a little frustrating!), and a few butt-ugly implementations are suggested.

I just wondered if it would be simpler to make the function accept a tuple, as the conversion that way is easier. But this implies that all functions should accept tuples as arguments, for maximum flexibility, and so that just demonstrates the strangeness of not providing a built-in expansion of tuple to function argument pack.

Update: the link above doesn't work - try pasting this:

http://groups.google.com/group/comp.lang.c++.moderated/browse_thread/thread/750fa3815cdaac45/d8dc09e34bbb9661?lnk=gst&q=tuple+variadic#d8dc09e34bbb9661