How to get N-th type from a tuple?

Question

I want to make a template where I can input an index and it will give me the type at that index. I know I can do this with decltype(std::get(tup)) but

Answer 1

You can use a class template and partial specializations to do what you want. (Note that std::tuple_element does almost the same like the other answer says):

#include 
#include 

template 
struct get;

template 
struct get>
{
    using type = typename get>::type;
};

template 
struct get<0, std::tuple>
{
    using type = T;
};

int main()
{
    using var = std::tuple;
    using type = get<2, var>::type;

    static_assert(std::is_same::value, ""); // works
}