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| <Head> |
| <Title>Boost Graph Library: Visitor Concepts</Title> |
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| <H1><A NAME="sec:visitor-concepts"></A> |
| Visitor Concepts |
| </H1> |
| |
| <P> |
| The visitor concepts plays the same role in BGL as <a |
| href="http://www.sgi.com/tech/stl/functors.html">functors</a> |
| play in the STL. Functors provide a mechanism for extending an |
| algorithm; for customizing what is done at each step of the algorithm. |
| Visitors allow the user to insert their own operations at various |
| steps within a graph algorithm. Unlike the STL algorithms, graph |
| algorithms typically have multiple event points where one may want to |
| insert a call-back via a functor. Therefore visitors do not have a |
| single <tt>operator()</tt> method like a functor, but instead have |
| several methods that correspond to the various event points. Each |
| algorithm has a different set of event points, which are described by |
| the following visitor concepts: |
| |
| <ul> |
| <li> <a href="./BFSVisitor.html">BFS Visitor</a> |
| <li> <a href="./DFSVisitor.html">DFS Visitor</a> |
| <li> <a href="./DijkstraVisitor.html">Dijkstra Visitor</a> |
| <li> <a href="./BellmanFordVisitor.html">Bellman Ford Visitor</a> |
| <li> <a href="./AStarVisitor.html">A* Visitor</a> |
| <li> <a href="./EventVisitor.html">Event Visitor</a> |
| <li> <a href="./PlanarFaceVisitor.html">Planar Face Visitor</a> |
| <li> <a href="./TSPTourVisitor.html">TSP Tour Visitor</a> |
| </ul> |
| |
| |
| <br> |
| <HR> |
| <TABLE> |
| <TR valign=top> |
| <TD nowrap>Copyright © 2000-2001</TD><TD> |
| <A HREF="http://www.boost.org/people/jeremy_siek.htm">Jeremy Siek</A>, |
| Indiana University (<A |
| HREF="mailto:jsiek@osl.iu.edu">jsiek@osl.iu.edu</A>)<br> |
| <A HREF="http://www.boost.org/people/liequan_lee.htm">Lie-Quan Lee</A>, Indiana University (<A HREF="mailto:llee@cs.indiana.edu">llee@cs.indiana.edu</A>)<br> |
| <A HREF="http://www.osl.iu.edu/~lums">Andrew Lumsdaine</A>, |
| Indiana University (<A |
| HREF="mailto:lums@osl.iu.edu">lums@osl.iu.edu</A>) |
| </TD></TR></TABLE> |
| |
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