Chris@16: //=======================================================================
Chris@16: // Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
Chris@16: // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //=======================================================================
Chris@16: //
Chris@16: // Revision History:
Chris@16: //   01 April 2001: Modified to use new <boost/limits.hpp> header. (JMaddock)
Chris@16: //
Chris@16: #ifndef BOOST_GRAPH_GRAPH_SEARCH_VISITORS_HPP
Chris@16: #define BOOST_GRAPH_GRAPH_SEARCH_VISITORS_HPP
Chris@16: 
Chris@16: #include <iosfwd>
Chris@16: #include <boost/config.hpp>
Chris@16: #include <boost/type_traits/is_same.hpp>
Chris@16: #include <boost/mpl/bool.hpp>
Chris@16: #include <boost/property_map/property_map.hpp>
Chris@16: #include <boost/graph/graph_traits.hpp>
Chris@16: #include <boost/limits.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: 
Chris@16:   // This is a bit more convenient than std::numeric_limits because
Chris@16:   // you don't have to explicitly provide type T.
Chris@16:   template <class T>
Chris@16:   inline T numeric_limits_max(T) { return (std::numeric_limits<T>::max)(); }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // Event Tags
Chris@16: 
Chris@16:   namespace detail {
Chris@16:     // For partial specialization workaround
Chris@16:     enum event_visitor_enum
Chris@16:     { on_no_event_num,
Chris@16:       on_initialize_vertex_num, on_start_vertex_num,
Chris@16:       on_discover_vertex_num, on_finish_vertex_num, on_examine_vertex_num,
Chris@16:       on_examine_edge_num, on_tree_edge_num, on_non_tree_edge_num,
Chris@16:       on_gray_target_num, on_black_target_num,
Chris@16:       on_forward_or_cross_edge_num, on_back_edge_num, on_finish_edge_num,
Chris@16:       on_edge_relaxed_num, on_edge_not_relaxed_num,
Chris@16:       on_edge_minimized_num, on_edge_not_minimized_num
Chris@16:     };
Chris@16: 
Chris@16:     template<typename Event, typename Visitor>
Chris@16:     struct functor_to_visitor : Visitor
Chris@16:     {
Chris@16:       typedef Event event_filter;
Chris@16:       functor_to_visitor(const Visitor& visitor) : Visitor(visitor) {}
Chris@16:     };
Chris@16: 
Chris@16:   } // namespace detail
Chris@16: 
Chris@16:   struct on_no_event { enum { num = detail::on_no_event_num }; };
Chris@16: 
Chris@16:   struct on_initialize_vertex {
Chris@16:     enum { num = detail::on_initialize_vertex_num }; };
Chris@16:   struct on_start_vertex { enum { num = detail::on_start_vertex_num }; };
Chris@16:   struct on_discover_vertex { enum { num = detail::on_discover_vertex_num }; };
Chris@16:   struct on_examine_vertex { enum { num = detail::on_examine_vertex_num }; };
Chris@16:   struct on_finish_vertex { enum { num = detail::on_finish_vertex_num }; };
Chris@16: 
Chris@16:   struct on_examine_edge { enum { num = detail::on_examine_edge_num }; };
Chris@16:   struct on_tree_edge { enum { num = detail::on_tree_edge_num }; };
Chris@16:   struct on_non_tree_edge { enum { num = detail::on_non_tree_edge_num }; };
Chris@16:   struct on_gray_target { enum { num = detail::on_gray_target_num }; };
Chris@16:   struct on_black_target { enum { num = detail::on_black_target_num }; };
Chris@16:   struct on_forward_or_cross_edge {
Chris@16:     enum { num = detail::on_forward_or_cross_edge_num }; };
Chris@16:   struct on_back_edge { enum { num = detail::on_back_edge_num }; };
Chris@16:   struct on_finish_edge { enum { num = detail::on_finish_edge_num }; };
Chris@16: 
Chris@16:   struct on_edge_relaxed { enum { num = detail::on_edge_relaxed_num }; };
Chris@16:   struct on_edge_not_relaxed {
Chris@16:     enum { num = detail::on_edge_not_relaxed_num }; };
Chris@16:   struct on_edge_minimized { enum { num = detail::on_edge_minimized_num }; };
Chris@16:   struct on_edge_not_minimized {
Chris@16:     enum { num = detail::on_edge_not_minimized_num }; };
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // base_visitor and null_visitor
Chris@16: 
Chris@16:   // needed for MSVC workaround
Chris@16:   template <class Visitor>
Chris@16:   struct base_visitor {
Chris@16:     typedef on_no_event event_filter;
Chris@16:     template <class T, class Graph>
Chris@16:     void operator()(T, Graph&) { }
Chris@16:   };
Chris@16: 
Chris@16:   struct null_visitor : public base_visitor<null_visitor> {
Chris@16:     typedef on_no_event event_filter;
Chris@16:     template <class T, class Graph>
Chris@16:     void operator()(T, Graph&) { }
Chris@16:   };
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // The invoke_visitors() function
Chris@16: 
Chris@16:   namespace detail {
Chris@16:     template <class Visitor, class T, class Graph>
Chris@16:     inline void invoke_dispatch(Visitor& v, T x, Graph& g, mpl::true_) {
Chris@16:        v(x, g);
Chris@16:     }
Chris@16: 
Chris@16:     template <class Visitor, class T, class Graph>
Chris@16:     inline void invoke_dispatch(Visitor&, T, Graph&, mpl::false_)
Chris@16:     { }
Chris@16:   } // namespace detail
Chris@16: 
Chris@16:   template <class Visitor, class Rest, class T, class Graph, class Tag>
Chris@16:   inline void
Chris@16:   invoke_visitors(std::pair<Visitor, Rest>& vlist, T x, Graph& g, Tag tag) {
Chris@16:     typedef typename Visitor::event_filter Category;
Chris@16:     typedef typename is_same<Category, Tag>::type IsSameTag;
Chris@16:     detail::invoke_dispatch(vlist.first, x, g, IsSameTag());
Chris@16:     invoke_visitors(vlist.second, x, g, tag);
Chris@16:   }
Chris@16:   template <class Visitor, class T, class Graph, class Tag>
Chris@16:   inline void
Chris@16:   invoke_visitors(Visitor& v, T x, Graph& g, Tag) {
Chris@16:     typedef typename Visitor::event_filter Category;
Chris@16:     typedef typename is_same<Category, Tag>::type IsSameTag;
Chris@16:     detail::invoke_dispatch(v, x, g, IsSameTag());
Chris@16:   }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // predecessor_recorder
Chris@16: 
Chris@16:   template <class PredecessorMap, class Tag>
Chris@16:   struct predecessor_recorder
Chris@16:     : public base_visitor<predecessor_recorder<PredecessorMap, Tag> >
Chris@16:   {
Chris@16:     typedef Tag event_filter;
Chris@16:     predecessor_recorder(PredecessorMap pa) : m_predecessor(pa) { }
Chris@16:     template <class Edge, class Graph>
Chris@16:     void operator()(Edge e, const Graph& g) {
Chris@16:       put(m_predecessor, target(e, g), source(e, g));
Chris@16:     }
Chris@16:     PredecessorMap m_predecessor;
Chris@16:   };
Chris@16:   template <class PredecessorMap, class Tag>
Chris@16:   predecessor_recorder<PredecessorMap, Tag>
Chris@16:   record_predecessors(PredecessorMap pa, Tag) {
Chris@16:     return predecessor_recorder<PredecessorMap, Tag> (pa);
Chris@16:   }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // edge_predecessor_recorder
Chris@16: 
Chris@16:   template <class PredEdgeMap, class Tag>
Chris@16:   struct edge_predecessor_recorder
Chris@16:     : public base_visitor<edge_predecessor_recorder<PredEdgeMap, Tag> >
Chris@16:   {
Chris@16:     typedef Tag event_filter;
Chris@16:     edge_predecessor_recorder(PredEdgeMap pa) : m_predecessor(pa) { }
Chris@16:     template <class Edge, class Graph>
Chris@16:     void operator()(Edge e, const Graph& g) {
Chris@16:       put(m_predecessor, target(e, g), e);
Chris@16:     }
Chris@16:     PredEdgeMap m_predecessor;
Chris@16:   };
Chris@16:   template <class PredEdgeMap, class Tag>
Chris@16:   edge_predecessor_recorder<PredEdgeMap, Tag>
Chris@16:   record_edge_predecessors(PredEdgeMap pa, Tag) {
Chris@16:     return edge_predecessor_recorder<PredEdgeMap, Tag> (pa);
Chris@16:   }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // distance_recorder
Chris@16: 
Chris@16:   template <class DistanceMap, class Tag>
Chris@16:   struct distance_recorder
Chris@16:     : public base_visitor<distance_recorder<DistanceMap, Tag> >
Chris@16:   {
Chris@16:     typedef Tag event_filter;
Chris@16:     distance_recorder(DistanceMap pa) : m_distance(pa) { }
Chris@16:     template <class Edge, class Graph>
Chris@16:     void operator()(Edge e, const Graph& g) {
Chris@16:       typename graph_traits<Graph>::vertex_descriptor
Chris@16:         u = source(e, g), v = target(e, g);
Chris@16:       put(m_distance, v, get(m_distance, u) + 1);
Chris@16:     }
Chris@16:     DistanceMap m_distance;
Chris@16:   };
Chris@16:   template <class DistanceMap, class Tag>
Chris@16:   distance_recorder<DistanceMap, Tag>
Chris@16:   record_distances(DistanceMap pa, Tag) {
Chris@16:     return distance_recorder<DistanceMap, Tag> (pa);
Chris@16:   }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // time_stamper
Chris@16: 
Chris@16: 
Chris@16:   template <class TimeMap, class TimeT, class Tag>
Chris@16:   struct time_stamper
Chris@16:     : public base_visitor<time_stamper<TimeMap, TimeT, Tag> >
Chris@16:   {
Chris@16:     typedef Tag event_filter;
Chris@16:     time_stamper(TimeMap pa, TimeT& t) : m_time_pa(pa), m_time(t) { }
Chris@16:     template <class Vertex, class Graph>
Chris@16:     void operator()(Vertex u, const Graph&) {
Chris@16:       put(m_time_pa, u, ++m_time);
Chris@16:     }
Chris@16:     TimeMap m_time_pa;
Chris@16:     TimeT& m_time;
Chris@16:   };
Chris@16:   template <class TimeMap, class TimeT, class Tag>
Chris@16:   time_stamper<TimeMap, TimeT, Tag>
Chris@16:   stamp_times(TimeMap pa, TimeT& time_counter, Tag) {
Chris@16:     return time_stamper<TimeMap, TimeT, Tag>(pa, time_counter);
Chris@16:   }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // property_writer
Chris@16: 
Chris@16:   template <class PA, class OutputIterator, class Tag>
Chris@16:   struct property_writer
Chris@16:     : public base_visitor<property_writer<PA, OutputIterator, Tag> >
Chris@16:   {
Chris@16:     typedef Tag event_filter;
Chris@16: 
Chris@16:     property_writer(PA pa, OutputIterator out) : m_pa(pa), m_out(out) { }
Chris@16: 
Chris@16:     template <class T, class Graph>
Chris@16:     void operator()(T x, Graph&) { *m_out++ = get(m_pa, x); }
Chris@16:     PA m_pa;
Chris@16:     OutputIterator m_out;
Chris@16:   };
Chris@16:   template <class PA, class OutputIterator, class Tag>
Chris@16:   property_writer<PA, OutputIterator, Tag>
Chris@16:   write_property(PA pa, OutputIterator out, Tag) {
Chris@16:     return property_writer<PA, OutputIterator, Tag>(pa, out);
Chris@16:   }
Chris@16: 
Chris@16:   //========================================================================
Chris@16:   // property_put
Chris@16: 
Chris@16:     /**
Chris@16:      * Functor which just sets a given value to a vertex or edge in a property map.
Chris@16:      */
Chris@16: 
Chris@16:   template <typename PropertyMap, typename EventTag>
Chris@16:   struct property_put
Chris@16:   {
Chris@16:     typedef EventTag event_filter;
Chris@16:     
Chris@16:     property_put (PropertyMap property_map,
Chris@16:                   typename property_traits <PropertyMap>::value_type value) :
Chris@16:       property_map_ (property_map), value_ (value)
Chris@16:     {}
Chris@16: 
Chris@16:     template <typename VertexOrEdge, typename Graph>
Chris@16:     void operator() (VertexOrEdge v, const Graph&)
Chris@16:     {
Chris@16:       put (property_map_, v, value_);
Chris@16:     }
Chris@16: 
Chris@16:   private:
Chris@16:     PropertyMap property_map_;
Chris@16:     typename property_traits <PropertyMap>::value_type value_;
Chris@16:   };
Chris@16: 
Chris@16:   /**
Chris@16:    * Creates a property_put functor which just sets a given value to a vertex or edge.
Chris@16:    * 
Chris@16:    * @param property_map Given writeable property map 
Chris@16:    * @param value Fixed value of the map
Chris@16:    * @param tag Event Filter
Chris@16:    * @return The functor.
Chris@16:    */
Chris@16: 
Chris@16:     template <typename PropertyMap, typename EventTag>
Chris@16:     inline property_put <PropertyMap, EventTag>
Chris@16:     put_property (PropertyMap property_map,
Chris@16:                   typename property_traits <PropertyMap>::value_type value,
Chris@16:                   EventTag)
Chris@16:     {
Chris@16:       return property_put <PropertyMap, EventTag> (property_map, value);
Chris@16:     }
Chris@16: 
Chris@16: #define BOOST_GRAPH_EVENT_STUB(Event,Kind)                                 \
Chris@16:     typedef ::boost::Event Event##_type;                                   \
Chris@16:     template<typename Visitor>                                             \
Chris@16:     Kind##_visitor<std::pair<detail::functor_to_visitor<Event##_type,      \
Chris@16:                                                      Visitor>, Visitors> > \
Chris@16:     do_##Event(Visitor visitor)                                            \
Chris@16:     {                                                                      \
Chris@16:       typedef std::pair<detail::functor_to_visitor<Event##_type, Visitor>, \
Chris@16:                         Visitors> visitor_list;                            \
Chris@16:       typedef Kind##_visitor<visitor_list> result_type;                    \
Chris@16:       return result_type(visitor_list(visitor, m_vis));                    \
Chris@16:     }
Chris@16: 
Chris@16: } /* namespace boost */
Chris@16: 
Chris@16: #endif