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Diffstat (limited to 'boost/graph/graph_archetypes.hpp')
-rw-r--r-- | boost/graph/graph_archetypes.hpp | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/boost/graph/graph_archetypes.hpp b/boost/graph/graph_archetypes.hpp index 9b364bb814..81f9c2c8a8 100644 --- a/boost/graph/graph_archetypes.hpp +++ b/boost/graph/graph_archetypes.hpp @@ -53,6 +53,8 @@ namespace boost { // should use a different namespace for this typedef void in_edge_iterator; typedef void vertex_iterator; typedef void edge_iterator; + + static vertex_descriptor null_vertex() {return vertex_descriptor();} }; template <typename V, typename D, typename P, typename B> V source(const typename incidence_graph_archetype<V,D,P,B>::edge_descriptor&, @@ -105,6 +107,8 @@ namespace boost { // should use a different namespace for this typedef void out_edge_iterator; typedef void vertex_iterator; typedef void edge_iterator; + + static vertex_descriptor null_vertex() {return vertex_descriptor();} }; template <typename V, typename D, typename P, typename B> @@ -154,6 +158,8 @@ namespace boost { // should use a different namespace for this typedef void in_edge_iterator; typedef void edge_iterator; + + static vertex_descriptor null_vertex() {return vertex_descriptor();} }; template <typename V, typename D, typename P, typename B> |