Someone has to make SOME backwards incompatible changes sometime. I

Someone has to make SOME backwards incompatible changes sometime. I
switched around the prev & next pointers in GList.

not. (Would this change make any functional difference? Discuss in a five
page paper. :-)

Actually, added g_list_position() - inverse of g_list_nth()

glib/ChangeLog

@@ -1,3 +1,9 @@
+1998-04-27  Elliot Lee  <sopwith@cuc.ml.org>
+
+	* glist.c (g_list_position): New function to find the position of
+	a link in a list - should be the inverse of g_list_nth(), but
+	haven't tested it so poof.
+
 Tue Apr  7 19:36:48 1998  Owen Taylor  <owt1@cornell.edu>
 
 	* gutils.c (g_direct_compare): Removed, because that's what

glib/glib.h

@@ -445,6 +445,8 @@ GList* g_list_remove_link (GList     *list,
 GList* g_list_reverse	  (GList     *list);
 GList* g_list_nth	  (GList     *list,
 			   guint      n);
+gint   g_list_position    (GList     *list,
+			   GList     *link);
 GList* g_list_find	  (GList     *list,
 			   gpointer   data);
 GList* g_list_last	  (GList     *list);

glib/glist.c

@@ -300,6 +300,21 @@ g_list_nth (GList *list,
   return list;
 }
 
+gint
+g_list_position (GList     *list,
+		 GList     *link)
+{
+  gint nth;
+  GList *curlink;
+  for(nth = 0, curlink = list; curlink; curlink = g_list_next(curlink), nth++)
+    {
+	if(curlink == link) return nth;
+    }
+
+  return -1;
+}
+
+
 GList*
 g_list_find (GList    *list,
 	     gpointer  data)

glib/testglib.c

@@ -126,6 +126,10 @@ main (int   argc,
 	g_error ("Regular insert failed");
     }
 
+  for (i = 0; i < 10; i++)
+    if(g_list_position(list, g_list_nth (list, i)) != i)
+      g_error("g_list_position does not seem to be the inverse of g_list_nth\n");
+
   g_list_free (list);
   list = NULL;