C++11 type alias of std::array with operators

Question

I have a c++11 type alias: using coord = std::array; Can I define the operator + for coord? How? I'd want to be able to do: coord a, b, c; a = {1.1, 2.0, 0}; b = {0, -1, 3.5}; c = a + b; // c = {1.1, 1.0, 3.5} JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

I wouln't recommend defining new operators for STL type, or any types that aren't in your control. I would suggest instead create your own types: struct coord { // reimplement operator[], fill, size, etc. friend constexpr auto operator+ (coord const& lhs, coord const& rhs) noexcept -> coord { // ... } private: std::array _coord; }; Or you could also shortcut your way around using operators and member function already defind in std::array: struct coord : private std::array { constexpr coord(double a, double b, double c) noexcept : array{a, b, c} {} using array::operator[]; using array::begin; using array::end; using array::fill; // other operators... friend constexpr auto operator+ (coord const& lhs, coord const& rhs) noexcept -> coord { // ... } }; Note: If you want to support structured binding and offer tuple like access to your coord class, then you must add overloads for get and specialize std::tuple_size and std::tuple_element: namespace std { template tuple_element { using type = double; }; tuple_size<::coord> : integral_constant {}; } template constexpr auto get(coord const& c) noexcept -> double const& { return c[n] } template constexpr auto get(coord& c) noexcept -> double& { return c[n]; } template constexpr auto get(coord&& c) noexcept -> double&& { return std::move(c[n]); } template constexpr auto get(coord const&& c) noexcept -> double const&& { return std::move(c[n]); } This code will allow that kind of code when you switch C++17 on: auto my_coord = coord{1.0, 2.0, 3.0}; auto [x, y, z] = my_coord;