Boost C++ Libraries

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bfs_visitor<EventVisitorList>

This class is an adapter that converts a list of EventVisitors (constructed using std::pair) into a BFSVisitor.

Example

This is an excerpt from examples/bfs.cpp where three event-visitors are combined to make a BFS visitor. The functions boost::record_distances, boost::record_predecessors, and copy_graph are all functions that create an event visitor.

  // Construct graph G and obtain the source vertex s ...

  boost::breadth_first_search(G, s,
   boost::make_bfs_visitor(
    std::make_pair(boost::record_distances(d, boost::on_tree_edge()),
    std::make_pair(boost::record_predecessors(p.begin(),
                                              boost::on_tree_edge()),
                   copy_graph(G_copy, boost::on_examine_edge())))) );

Model of

BFSVisitor

Template Parameters

Parameter Description Default

EventVisitorList A list of EventVisitor's created with std::pair. null_visitor

Parameter	Description	Default
`EventVisitorList`	A list of EventVisitor's created with `std::pair`.	`null_visitor`

Where Defined

boost/graph/breadth_first_search.hpp

Member Functions

This class implements all of the member functions required by BFSVisitor. In each function the appropriate event is dispatched to the EventVisitor in the EventVisitorList.

Non-Member Functions

Function	Description
`template <class EventVisitorList> bfs_visitor<EventVisitorList> make_bfs_visitor(EventVisitorList ev_list);`	Returns the event visitor list adapted to be a BFS visitor.