traits/accum0.hpp

The following code example is taken from the book
C++ Templates - The Complete Guide
by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002
© Copyright David Vandevoorde and Nicolai M. Josuttis 2002


#ifndef ACCUM_HPP
#define ACCUM_HPP

#include <iterator>

template <typename Iter>
inline
typename std::iterator_traits<Iter>::value_type 
accum (Iter start, Iter end)
{
    typedef typename std::iterator_traits<Iter>::value_type VT;

    VT total = VT();  // assume VT() actually creates a zero value
    while (start != end) {
        total += *start;
        ++start;
    }
    return total;
}

#endif // ACCUM_HPP