Ion Gaztañaga wrote:
I would like to depend only on TypeTraits but that's impossible, it brings MPL, Preprocessor, etc.
Regardless of what we ultimately do with TypeTraits, I think that a "core type traits" module with minimal dependencies (and no base classes) would be of at least interim value to people like Ion (and myself, for that matter) who would like to use type traits in f.ex. move and smart_ptr, but without the unnecessary dependencies on MPL, Preprocessor, TypeOf and Utility. In fact, Ion may already have started this work, inside his own module. The reasonable way forward, in my opinion, is for us to create a new module for core type traits, with (say) Ion and John Maddock as maintainers, to which then the implementations (and tests) of TypeTraits will gradually migrate. TypeTraits will then use the core traits to derive the trait value, then add all of the compatibility baggage on top for people who like that sort of thing.