variadic pack конструктор принимающий списки инициализации - C++ - Ответ 15476157

Matrix<double, 2, 2> m ({3, 4}, {5, 6});

    template <typename ...Args, typename = typename std::enable_if_t<IsIteratable<Args...>::value, void>>
    Matrix(Args... args){
        mat = {args...};
    }

template <typename T, typename ...OtherT>
struct IsIteratable{
    static const bool value = std::is_same_v<typename std::iterator_traits<typename T::iterator>::iterator_category(), std::random_access_iterator_tag()> || std::is_same_v<typename std::iterator_traits<typename T::iterator>::iterator_category(), std::bidirectional_iterator_tag()>
            && IsIteratable<OtherT...>::value;
};
 
template <typename T>
struct IsIteratable<T>{
    static const bool value = std::is_same_v<typename std::iterator_traits<typename T::iterator>::iterator_category(), std::random_access_iterator_tag()> || std::is_same_v<typename std::iterator_traits<typename T::iterator>::iterator_category(), std::bidirectional_iterator_tag()>;
};

Matrix<double, 2, 2> m (std::vector<double>{3, 4}, std::vector<double>{5, 6});

Matrix<double, 2, 2> m (std::initializer_list<double>{3, 4}, std::initializer_list<double>{5, 6});