[RFC] exports and linkage for TR1

[Paolo Carlini]

Hi Benjamin,
> I feel like TR1 is less in flux now. What do others think? Should we
> start exporting bits, and thus having to deal with compatibility?
> Thoughts about particular bits that should be avoided?
>   
In my opinion the issue isn't particularly urgent. In this sense: as you 
remind elsewhere, we could as well wait a bit more (probably the erase 
overloads will change in C++0x) and then add exports for the 
corresponding, more stable C++0x bits in namespace *std* instead of 
mixing now tr1 and std facilities. I have similar feelings about the 
tr1::type_traits issue: instead of using tr1:: names in the 
implementation of standard facilities, we can as well wait a bit more 
(see the message from Howard about a few bits still in flux) and then 
use the C++0x type_traits facilities in std.

Paolo.