boost/graph/graph_traits.hpp
//======================================================================= // Copyright 1997, 1998, 1999, 2000 University of Notre Dame. // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek // // Distributed under the Boost Software License, Version 1.0. (See // accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) //======================================================================= #ifndef BOOST_GRAPH_TRAITS_HPP #define BOOST_GRAPH_TRAITS_HPP #include <boost/config.hpp> #include <iterator> #include <utility> /* Primarily for std::pair */ #include <boost/tuple/tuple.hpp> #include <boost/mpl/if.hpp> #include <boost/mpl/bool.hpp> #include <boost/mpl/not.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/iterator/iterator_categories.hpp> #include <boost/iterator/iterator_adaptor.hpp> #include <boost/pending/property.hpp> #include <boost/detail/workaround.hpp> namespace boost { template <typename G> struct graph_traits { typedef typename G::vertex_descriptor vertex_descriptor; typedef typename G::edge_descriptor edge_descriptor; typedef typename G::adjacency_iterator adjacency_iterator; typedef typename G::out_edge_iterator out_edge_iterator; typedef typename G::in_edge_iterator in_edge_iterator; typedef typename G::vertex_iterator vertex_iterator; typedef typename G::edge_iterator edge_iterator; typedef typename G::directed_category directed_category; typedef typename G::edge_parallel_category edge_parallel_category; typedef typename G::traversal_category traversal_category; typedef typename G::vertices_size_type vertices_size_type; typedef typename G::edges_size_type edges_size_type; typedef typename G::degree_size_type degree_size_type; static inline vertex_descriptor null_vertex(); }; template <typename G> inline typename graph_traits<G>::vertex_descriptor graph_traits<G>::null_vertex() { return G::null_vertex(); } // directed_category tags struct directed_tag { }; struct undirected_tag { }; struct bidirectional_tag : public directed_tag { }; namespace detail { inline bool is_directed(directed_tag) { return true; } inline bool is_directed(undirected_tag) { return false; } } /** Return true if the given graph is directed. */ template <typename Graph> bool is_directed(const Graph&) { typedef typename graph_traits<Graph>::directed_category Cat; return detail::is_directed(Cat()); } /** Return true if the given graph is undirected. */ template <typename Graph> bool is_undirected(const Graph& g) { return !is_directed(g); } /** @name Directed/Undirected Graph Traits */ //@{ namespace graph_detail { template <typename Tag> struct is_directed_tag : mpl::bool_<is_convertible<Tag, directed_tag>::value> { }; } // namespace graph_detail template <typename Graph> struct is_directed_graph : graph_detail::is_directed_tag< typename graph_traits<Graph>::directed_category > { }; template <typename Graph> struct is_undirected_graph : mpl::not_< is_directed_graph<Graph> > { }; //@} // edge_parallel_category tags struct allow_parallel_edge_tag { }; struct disallow_parallel_edge_tag { }; namespace detail { inline bool allows_parallel(allow_parallel_edge_tag) { return true; } inline bool allows_parallel(disallow_parallel_edge_tag) { return false; } } template <typename Graph> bool allows_parallel_edges(const Graph&) { typedef typename graph_traits<Graph>::edge_parallel_category Cat; return detail::allows_parallel(Cat()); } /** @name Parallel Edges Traits */ //@{ /** * The is_multigraph metafunction returns true if the graph allows * parallel edges. Technically, a multigraph is a simple graph that * allows parallel edges, but since there are no traits for the allowance * or disallowance of loops, this is a moot point. */ template <typename Graph> struct is_multigraph : mpl::bool_< is_same< typename graph_traits<Graph>::edge_parallel_category, allow_parallel_edge_tag >::value > { }; //@} // traversal_category tags struct incidence_graph_tag { }; struct adjacency_graph_tag { }; struct bidirectional_graph_tag : virtual incidence_graph_tag { }; struct vertex_list_graph_tag { }; struct edge_list_graph_tag { }; struct adjacency_matrix_tag { }; /** @name Taversal Category Traits * These traits classify graph types by their supported methods of * vertex and edge traversal. */ //@{ template <typename Graph> struct is_incidence_graph : mpl::bool_< is_convertible< typename graph_traits<Graph>::traversal_category, incidence_graph_tag >::value > { }; template <typename Graph> struct is_bidirectional_graph : mpl::bool_< is_convertible< typename graph_traits<Graph>::traversal_category, bidirectional_graph_tag >::value > { }; template <typename Graph> struct is_vertex_list_graph : mpl::bool_< is_convertible< typename graph_traits<Graph>::traversal_category, vertex_list_graph_tag >::value > { }; template <typename Graph> struct is_edge_list_graph : mpl::bool_< is_convertible< typename graph_traits<Graph>::traversal_category, edge_list_graph_tag >::value > { }; template <typename Graph> struct is_adjacency_matrix : mpl::bool_< is_convertible< typename graph_traits<Graph>::traversal_category, adjacency_matrix_tag >::value > { }; //@} /** @name Directed Graph Traits * These metafunctions are used to fully classify directed vs. undirected * graphs. Recall that an undirected graph is also bidirectional, but it * cannot be both undirected and directed at the same time. */ //@{ template <typename Graph> struct is_directed_unidirectional_graph : mpl::and_< is_directed_graph<Graph>, mpl::not_< is_bidirectional_graph<Graph> > > { }; template <typename Graph> struct is_directed_bidirectional_graph : mpl::and_< is_directed_graph<Graph>, is_bidirectional_graph<Graph> > { }; //@} //?? not the right place ?? Lee typedef boost::forward_traversal_tag multi_pass_input_iterator_tag; // Forward declare graph_bundle_t property name (from // boost/graph/properties.hpp, which includes this file) for // bundled_result. enum graph_bundle_t {graph_bundle}; template <typename G> struct graph_property_type { typedef typename G::graph_property_type type; }; template <typename G> struct edge_property_type { typedef typename G::edge_property_type type; }; template <typename G> struct vertex_property_type { typedef typename G::vertex_property_type type; }; struct no_bundle { }; struct no_graph_bundle : no_bundle { }; struct no_vertex_bundle : no_bundle { }; struct no_edge_bundle : no_bundle { }; template<typename G> struct graph_bundle_type { typedef typename G::graph_bundled type; }; template<typename G> struct vertex_bundle_type { typedef typename G::vertex_bundled type; }; template<typename G> struct edge_bundle_type { typedef typename G::edge_bundled type; }; namespace graph { namespace detail { template<typename Graph, typename Descriptor> class bundled_result { typedef typename graph_traits<Graph>::vertex_descriptor Vertex; typedef typename mpl::if_c<(is_same<Descriptor, Vertex>::value), vertex_bundle_type<Graph>, edge_bundle_type<Graph> >::type bundler; public: typedef typename bundler::type type; }; template<typename Graph> class bundled_result<Graph, graph_bundle_t> { typedef typename graph_traits<Graph>::vertex_descriptor Vertex; typedef graph_bundle_type<Graph> bundler; public: typedef typename bundler::type type; }; } } // namespace graph::detail namespace graph_detail { // A helper metafunction for determining whether or not a type is // bundled. template <typename T> struct is_no_bundle : mpl::bool_<is_convertible<T, no_bundle>::value> { }; } // namespace graph_detail /** @name Graph Property Traits * These metafunctions (along with those above), can be used to access the * vertex and edge properties (bundled or otherwise) of vertices and * edges. */ //@{ template<typename Graph> struct has_graph_property : mpl::not_< typename detail::is_no_property< typename graph_property_type<Graph>::type >::type >::type { }; template<typename Graph> struct has_bundled_graph_property : mpl::not_< graph_detail::is_no_bundle<typename graph_bundle_type<Graph>::type> > { }; template <typename Graph> struct has_vertex_property : mpl::not_< typename detail::is_no_property<typename vertex_property_type<Graph>::type> >::type { }; template <typename Graph> struct has_bundled_vertex_property : mpl::not_< graph_detail::is_no_bundle<typename vertex_bundle_type<Graph>::type> > { }; template <typename Graph> struct has_edge_property : mpl::not_< typename detail::is_no_property<typename edge_property_type<Graph>::type> >::type { }; template <typename Graph> struct has_bundled_edge_property : mpl::not_< graph_detail::is_no_bundle<typename edge_bundle_type<Graph>::type> > { }; //@} } // namespace boost // Since pair is in namespace std, Koenig lookup will find source and // target if they are also defined in namespace std. This is illegal, // but the alternative is to put source and target in the global // namespace which causes name conflicts with other libraries (like // SUIF). namespace std { /* Some helper functions for dealing with pairs as edges */ template <class T, class G> T source(pair<T,T> p, const G&) { return p.first; } template <class T, class G> T target(pair<T,T> p, const G&) { return p.second; } } #if defined(__GNUC__) && defined(__SGI_STL_PORT) // For some reason g++ with STLport does not see the above definition // of source() and target() unless we bring them into the boost // namespace. namespace boost { using std::source; using std::target; } #endif #endif // BOOST_GRAPH_TRAITS_HPP