2009/12/6 Frédéric Bron <frederic.bron@m4x.org>
>> How would I implement the operator_plus_exists class?
>
> Such a traits have been added to type_traits, check the trunk or the vault.

I am working on adding such traits for comparison operators
(operator<, operator>...) You can have a look at a working draft here:
https://svn.boost.org/trac/boost/browser/sandbox/type_traits
Look at is_less_comparable.hpp


Thanks, for the record I actually finally got mine working.  I figured out at least 5 ways that *should* have worked, but MSVC wouldn't compile it.  But I did hit upon one that worked, but it's over on the boost dev mailing list now. 

Zach