Changes in lemon/core.h [1107:2b6bffe0e7e8:1111:c8fce9beb46a] in lemon

File:

• lemon/core.h (modified) (1 diff)

lemon/core.h

@@ -447 +447 @@
 
   }
+
+  /// \brief Check whether a graph is undirected.
+  ///
+  /// This function returns \c true if the given graph is undirected.
+#ifdef DOXYGEN
+  template <typename GR>
+  bool undirected(const GR& g) { return false; }
+#else
+  template <typename GR>
+  typename enable_if<UndirectedTagIndicator<GR>, bool>::type
+  undirected(const GR&) {
+    return true;
+  }
+  template <typename GR>
+  typename disable_if<UndirectedTagIndicator<GR>, bool>::type
+  undirected(const GR&) {
+    return false;
+  }
+#endif
 
   /// \brief Class to copy a digraph.