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
template<typename T, typename U>
struct MultiplyT;
template<typename T, T Value1, T Value2>
struct MultiplyT<CTValue<T, Value1>, CTValue<T, Value2>> {
public:
using Type = CTValue<T, Value1 * Value2>;
};
template<typename T, typename U>
using Multiply = typename MultiplyT<T, U>::Type;