From 451823c22d77ae57160316837621b0501a3629f9 Mon Sep 17 00:00:00 2001
From: Boris Kolpackov <boris@codesynthesis.com>
Date: Thu, 15 Apr 2010 09:04:45 +0200
Subject: Add support for resetting nodes/edges and deleting nodes

---
 cutl/container/graph.hxx | 53 +++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/cutl/container/graph.hxx b/cutl/container/graph.hxx
index 2b796a1..9244351 100644
--- a/cutl/container/graph.hxx
+++ b/cutl/container/graph.hxx
@@ -16,6 +16,7 @@ namespace cutl
   namespace container
   {
     struct no_edge: exception {};
+    struct no_node: exception {};
 
     template <typename N, typename E>
     class graph
@@ -84,10 +85,6 @@ namespace cutl
       new_node (A0 const&, A1 const&, A2 const&, A3 const&, A4 const&,
                 A5 const&, A6 const&, A7 const&, A8 const&, A9 const&);
 
-      // template <typename T>
-      // void
-      // delete_node (T& node);
-
     public:
       template <typename T, typename L, typename R>
       T&
@@ -127,10 +124,56 @@ namespace cutl
       new_edge (L&, R&, A0 const&, A1 const&, A2 const&, A3 const&,
                 A4 const&, A5 const&);
 
+      // Functions to reset edge's nodes.
+      //
+    public:
+      template <typename TE, typename TN>
+      void
+      reset_left_node (TE& edge, TN& node)
+      {
+        edge.set_left_node (node);
+      }
+
+      template <typename TE, typename TN>
+      void
+      reset_right_node (TE& edge, TN& node)
+      {
+        edge.set_right_node (node);
+      }
+
+      // Functions to add edges to a node.
+      //
+    public:
+      template <typename TN, typename TE>
+      void
+      add_edge_left (TN& node, TE& edge)
+      {
+        node.add_edge_left (edge);
+      }
+
+      template <typename TN, typename TE>
+      void
+      add_edge_right (TN& node, TE& edge)
+      {
+        node.add_edge_right (edge);
+      }
+
+      // Functions to delete edges and nodes. In order to delete a
+      // a node without leaving any dangling edges you need to make
+      // sure that each edge pointing to it is either deleted or reset
+      // to some other node.
+      //
     public:
       template <typename T, typename L, typename R>
       void
-      delete_edge (L&, R&, T& edge);
+      delete_edge (L& left_node, R& right_node, T& edge);
+
+      void
+      delete_node (node_base& node)
+      {
+        if (nodes_.erase (&node) == 0)
+          throw no_node ();
+      }
 
     public:
       graph () {}
-- 
cgit v1.1