#include #include #include #include #include template struct identity { typedef T type; }; template struct best_type { typedef typename std::conditional< sizeof(Head) >= sizeof(T), identity, best_type >::type::type type; }; template struct type_to_integral { typedef typename best_type::type type; static_assert(std::is_integral::value, "Type is too large"); }; int main() { static_assert(std::is_same::type, uint8_t>::value, "Fail"); static_assert(std::is_same::type, uint16_t>::value, "Fail"); static_assert(std::is_same::type, uint32_t>::value, "Fail"); static_assert(std::is_same::type, uint64_t>::value, "Fail"); }