Produce std::tuple of same type in compile time given its length by a template argument

Question

In c++, how can I implement a function with an int template argument indicating the tuple length and produce a std::tuple with that length?

E.g.

func<         


        

Answer 1

Here is a recursive solution with alias template and it's implementable in C++11:

template  
struct tuple_n{
    template< typename...Args> using type = typename tuple_n::template type;
};

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

For example if we want "tuple of 3 doubles" we can write:

tuple_of<3, double> t;