Hi folks, I would like to propose to your review the following addition to the type_traits library. The addition is attached to this email and also available in the sandbox at https://svn.boost.org/trac/boost/browser/sandbox/type_traits The purpose of the addition is to add type traits to detect if type T is comparable in the sens of <, <=, >, >=, == or != operators, i.e. if t1<t2 has a sens when t1 and t2 are of type T (same for <=, >, >=, ==, !=). The following traits are added: is_equal_to_comparable<T> is_greater_comparable<T> is_greater_equal_comparable<T> is_less_comparable<T> is_less_equal_comparable<T> is_not_equal_to_comparable<T> The names are based on the corresponding names of the standard template library (<functional> header, section 20.3.3 of the standard). The compilation has been tested with g++ 4.3.2 and icpc 10.0 on linux 64 bits, g++ 3.4.4 on cygwin, mingw32 3.4.4 on cygwin. I must add that I did not invent the code (I obtained some help from the boost mailing list) but I put it together in a form that should be acceptable to boost. Regards, Frédéric