[boost] Tick: Trait instrospection library for C++14

Hi, I developed a trait introspection library for C++14 based on Eric Niebler's concept checking, here: https://github.com/pfultz2/Tick So you can build a simple `is_incrementable` trait like this:     TICK_TRAIT(is_incrementable)     {         template<class T>         auto requires(T&& x) -> TICK_VALID(             x++,             ++x         );     }; Then use it like this:     static_assert(is_incrementable<T>(), "Not incrementable"); Also, you can validate the return of an expressions like this:     TICK_TRAIT(is_equality_comparable)     {         template         auto requires(T&& x, U&& y) -> TICK_VALID(             returns<bool>(x == y),             returns<bool>(x != y)         );     }; You can also match against another trait using placeholder expressions:     TICK_TRAIT(is_incrementable)     {         template<class T>         auto requires(T&& x) -> TICK_VALID(             return>(x++),             return>(++x)         );     }; Any feedback would be appreciated. Also, I don't knw if there would be any interest in incorporating this into boost. Thanks, Paul