[v3] Variadic templates, third revision (3/3)

[Benjamin Kosnik]

Hey Doug. Sorry for the delay.

I'm ok with this patch going in as soon as the compiler bits are
cleared for check in. I'm also hoping that will happen soon-ish, and
that when this stuff gets checked in you'll update gcc-4.3 with this
exciting development.

My only thought is how to use the __GXX_EXPERIMENTAL_CPP0X__ macro
with the TR1 includes that have been altered. I think that this should
definitely happen.

My suggestion is to do:

#ifndef __GXX_EXPERIMENTAL_CPP0X__
#error This file makes use of experimental C++0x features, and must be
compiled with -std=gnu++0x.
#endif

At the top of

tr1/tuple
tr1/functional

Thoughts?

Again, nice work. Thanks for this!

-benjamin