The following code example is taken from the book
C++ Templates - The Complete Guide, 2nd Edition
by David Vandevoorde, Nicolai M. Josuttis, and Douglas Gregor,
Addison-Wesley, 2017
© Copyright David Vandevoorde, Nicolai M. Josuttis, Douglas Gregor 2017
// recursive case:
template<typename Head, typename... Tail>
class Tuple<Head, Tail...> : private Tuple<Tail...>
{
private:
Head head;
public:
Head& getHead() { return head; }
Head const& getHead() const { return head; }
Tuple<Tail...>& getTail() { return *this; }
Tuple<Tail...> const& getTail() const { return *this; }
};