/* The following code example is taken from the book * "C++ Templates - The Complete Guide" * by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002 * * (C) Copyright David Vandevoorde and Nicolai M. Josuttis 2002. * Permission to copy, use, modify, sell and distribute this software * is granted provided this copyright notice appears in all copies. * This software is provided "as is" without express or implied * warranty, and with no claim as to its suitability for any purpose. */#ifndef ACCUM_HPP#define ACCUM_HPP#include "accumtraits4.hpp"#include "sumpolicy3.hpp"template <typename T,          typename Policy = SumPolicy<>,          typename Traits = AccumulationTraits<T> >class Accum {  public:    typedef typename Traits::AccT AccT;    static AccT accum (T const* beg, T const* end) {        AccT total = Traits::zero();        while (beg != end) {            Policy::accumulate(total, *beg);            ++beg;        }        return total;    }};#endif // ACCUM_HPP