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
#ifndef ACCUM_HPP
#define ACCUM_HPP
#include "accumtraits3.hpp"
template<typename T>
auto accum (T const* beg, T const* end)
{
// return type is traits of the element type
using AccT = typename AccumulationTraits<T>::AccT;
AccT total = AccumulationTraits<T>::zero; // init total by trait value
while (beg != end) {
total += *beg;
++beg;
}
return total;
}
#endif // ACCUM_HPP