// arch-tag: dc0a48cf-c241-4480-b722-6e181cbd9fca
/*
 * (C) Copyright Neal D. Becker (2004)
 * 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 strided_iterator_hpp
#define strided_iterator_hpp

#include <boost/iterator/iterator_adaptor.hpp>
#include <iterator>

namespace boost {

  template<typename BaseIterator>
  class strided_iterator : public boost::iterator_adaptor<
    strided_iterator<BaseIterator>,
    BaseIterator> {


    friend class iterator_core_access;

  public:

    typedef typename boost::iterator_adaptor<strided_iterator<BaseIterator>,BaseIterator> super_t;
    typedef typename std::iterator_traits<BaseIterator>::difference_type difference_type;

    strided_iterator() {}

    explicit strided_iterator (BaseIterator _base, size_t _stride) :
      super_t (_base), stride (_stride) {}

    void increment()
    { this->base_reference() += stride; }

    void decrement()
    { this->base_reference() -= stride; }

    void advance(difference_type n)
    { this->base_reference() += n*stride; }

    difference_type
    distance_to(strided_iterator<BaseIterator> const& y) const 
    { return (y.base_reference()-this->base_reference())/stride; }

      
  private:

    const int stride;
  };

  template<typename BaseIterator>
  strided_iterator<BaseIterator> make_strided_iterator(BaseIterator const& begin, int stride) {
    return strided_iterator<BaseIterator> (begin, stride);
  }

    

} // namespace boost

#endif