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>
struct AccumulationTraits;
template<>
struct AccumulationTraits<char> {
using AccT = int;
static constexpr AccT zero() {
return 0;
}
};
template<>
struct AccumulationTraits<short> {
using AccT = int;
static constexpr AccT zero() {
return 0;
}
};
template<>
struct AccumulationTraits<int> {
using AccT = long;
static constexpr AccT zero() {
return 0;
}
};
template<>
struct AccumulationTraits<unsigned int> {
using AccT = unsigned long;
static constexpr AccT zero() {
return 0;
}
};
template<>
struct AccumulationTraits<float> {
using AccT = double;
static constexpr AccT zero() {
return 0;
}
};
//...