Making a tuple of nested types [duplicate]

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• Where and why do I have to put the “template” and “typename” keywords? 5 answers

I have some classes A and B:

struct A
{
    typedef int value_type;
};
struct B
{
    typedef float value_type;
};

I want to make a tuple of A::value_type and B::value type via variadic template. I am expecting something like this:

template<typename ...T>
struct my_tuple
{
     typedef std::tuple<T::value_type...> tuple_type;
};

This doesnt compile. How can I make such kind of tuple?