ceph/src/boost/boost/graph/detail/incremental_components.hpp

   1 //=======================================================================
   2 // Copyright 2002 Indiana University.
   3 // Copyright 2009 Trustees of Indiana University.
   4 // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek, Michael Hansen
   5 //
   6 // Distributed under the Boost Software License, Version 1.0. (See
   7 // accompanying file LICENSE_1_0.txt or copy at
   8 // http://www.boost.org/LICENSE_1_0.txt)
   9 //=======================================================================
  10
  11 #ifndef BOOST_GRAPH_DETAIL_INCREMENTAL_COMPONENTS_HPP
  12 #define BOOST_GRAPH_DETAIL_INCREMENTAL_COMPONENTS_HPP
  13
  14 #include <boost/operators.hpp>
  15
  16 namespace boost {
  17
  18   namespace detail {
  19
  20     // Iterator for a component index linked list.  The contents of
  21     // each array element represent the next index in the list.  A
  22     // special value (the maximum index + 1) is used to terminate a
  23     // list.
  24     template <typename IndexRandomAccessIterator>
  25     class component_index_iterator :
  26       boost::forward_iterator_helper<component_index_iterator<IndexRandomAccessIterator>,
  27                                      typename std::iterator_traits<IndexRandomAccessIterator>::value_type,
  28                                      typename std::iterator_traits<IndexRandomAccessIterator>::difference_type,
  29                                      typename std::iterator_traits<IndexRandomAccessIterator>::pointer,
  30                                      typename std::iterator_traits<IndexRandomAccessIterator>::reference> {
  31
  32     private:
  33       typedef component_index_iterator<IndexRandomAccessIterator> self;
  34
  35     public:
  36       typedef std::forward_iterator_tag iterator_category;
  37       typedef typename std::iterator_traits<IndexRandomAccessIterator>::value_type value_type;
  38       typedef typename std::iterator_traits<IndexRandomAccessIterator>::difference_type reference;
  39       typedef typename std::iterator_traits<IndexRandomAccessIterator>::pointer pointer;
  40       typedef typename std::iterator_traits<IndexRandomAccessIterator>::reference difference_type;
  41
  42       // Constructor for "begin" iterator
  43       component_index_iterator(IndexRandomAccessIterator index_iterator,
  44                                value_type begin_index) :
  45         m_index_iterator(index_iterator),
  46         m_current_index(begin_index) { }
  47
  48       // Constructor for "end" iterator (end_index should be the linked
  49       // list terminator).
  50       component_index_iterator(value_type end_index) :
  51         m_current_index(end_index) { }
  52
  53       inline value_type operator*() const {
  54         return (m_current_index);
  55       }
  56
  57       self& operator++() {
  58         // Move to the next element in the linked list
  59         m_current_index = m_index_iterator[m_current_index];
  60         return (*this);
  61       }
  62
  63       bool operator==(const self& other_iterator) const {
  64         return (m_current_index == *other_iterator);
  65       }
  66
  67     protected:
  68       IndexRandomAccessIterator m_index_iterator;
  69       value_type m_current_index;
  70
  71     }; // class component_index_iterator
  72
  73   } // namespace detail
  74
  75 } // namespace detail
  76
  77 #endif // BOOST_GRAPH_DETAIL_INCREMENTAL_COMPONENTS_HPP