Create compile time int lookup table

int_map.cpp

template <int Val>
struct int_const : std::integral_constant<int, Val> {};

template <typename In, typename T>
struct getMappedOutput;

template <typename In, typename Left, typename Right, typename ...Tail>
struct getMappedOutput<In, std::tuple<Left, Right, Tail...>>
     : getMappedOutput<In, std::tuple<Tail...>>
{
};

template <typename In, typename Right, typename ...Tail>
struct getMappedOutput<In, std::tuple<In, Right, Tail...>>
{
    static constexpr auto value = Right::value;
};

int main()
{
    using lookup = std::tuple<int_const<0>, int_const<1>, int_const<1>, int_const<0>>;
    auto result = getMappedOutput<int_const<0>, lookup>::value;
    return result;
}