Ja concepts sind schon toll ;)
Grüße an euIRCnet #c++
enum class A {aa, bb}; enum class B {bb}; enum class C {aa, bb}; template<typename T> struct Isso { const static bool value = false; }; template<typename T> requires T::aa == T::aa struct Isso<T> { const static bool value = true; }; static_assert(Isso<A>::value); static_assert(Isso<B>::value == false); static_assert(Isso<C>::value);