[Boost-bugs] [Boost C++ Libraries] #9730: copy_graph doesn't use graph_traits

Subject: [Boost-bugs] [Boost C++ Libraries] #9730: copy_graph doesn't use graph_traits
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-03-02 13:44:49

#9730: copy_graph doesn't use graph_traits
-----------------------------------------------+----------------------
 Reporter:  Masahiro Nawata <kamo.tanabota@…>  |      Owner:  jewillco
     Type:  Bugs                               |     Status:  new
Milestone:  To Be Determined                   |  Component:  graph
  Version:  Boost 1.55.0                       |   Severity:  Problem
 Keywords:                                     |
-----------------------------------------------+----------------------
 copy_graph doesn't use graph_traits internally. Therefore, classes which
 don't have traversal_category and directed_category, such as std::vector
 or SGB, are not used as the source graph.

 follow code is compile error:
 {{{
 #include <vector>
 #include <list>
 #include <boost/graph/adjacency_list.hpp>
 #include <boost/graph/vector_as_graph.hpp>
 #include <boost/graph/copy.hpp>

 int main()
 {
         using VectorGraph = std::vector<std::list<int>>;
         auto vgraph = VectorGraph{{1, 2, 3}, {3, 5}, {5}, {4}, {0, 2},
 {0}};
         using Graph = boost::adjacency_list<>;
         auto graph = Graph{};
         boost::copy_graph(vgraph, graph
                         , boost::vertex_copy([](
 boost::graph_traits<VectorGraph>::vertex_descriptor
                                         ,
 boost::graph_traits<Graph>::vertex_descriptor) {})
                         . edge_copy([](
 boost::graph_traits<VectorGraph>::edge_descriptor
                                         ,
 boost::graph_traits<Graph>::edge_descriptor) {})
         );
 }
 }}}

 patch is here
 {{{
 --- /usr/local/include/boost/graph/copy.hpp     2014-03-02
 21:44:55.000000000 +0900
 +++ copy.hpp    2014-03-02 21:45:05.000000000 +0900
 @@ -248,8 +248,8 @@

      template <class Graph>
      struct choose_graph_copy {
 -      typedef typename Graph::traversal_category Trv;
 -      typedef typename Graph::directed_category Dr;
 +      typedef typename graph_traits<Graph>::traversal_category Trv;
 +      typedef typename graph_traits<Graph>::directed_category Dr;
        enum { algo =
               (is_convertible<Trv, vertex_list_graph_tag>::value
                && is_convertible<Trv, edge_list_graph_tag>::value)
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9730>
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