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// (C) Copyright David Abrahams and Jeremy Siek 2000-2001. 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.
// Revision History:
// 04 Jan 2001  Factored counting_iterator stuff into
//              boost/counting_iterator.hpp (David Abrahams)


#include <boost/config.hpp>
#include <boost/iterator/counting_iterator.hpp>

namespace boost {

// Counting Iterator and Integer Range Class

template <class IntegerType>
struct integer_range {
    typedef counting_iterator<IntegerType> iterator;

    typedef iterator const_iterator;
    typedef IntegerType value_type;
    typedef std::ptrdiff_t difference_type;
    typedef IntegerType reference;
    typedef IntegerType const_reference;
    typedef const IntegerType* pointer;
    typedef const IntegerType* const_pointer;
    typedef IntegerType size_type;

    integer_range(IntegerType start, IntegerType finish)
        : m_start(start), m_finish(finish) { }

    iterator begin() const { return iterator(m_start); }
    iterator end() const { return iterator(m_finish); }
    size_type size() const { return m_finish - m_start; }
    bool empty() const { return m_finish == m_start; }
    void swap(integer_range& x) {
        std::swap(m_start, x.m_start);
        std::swap(m_finish, x.m_finish);
    IntegerType m_start, m_finish;

template <class IntegerType>
inline integer_range<IntegerType>
make_integer_range(IntegerType first, IntegerType last)
  return integer_range<IntegerType>(first, last);

} // namespace boost