thm_deps: sort result;

--- a/src/Pure/Thy/thm_deps.ML	Mon Feb 25 19:38:48 2008 +0100
+++ b/src/Pure/Thy/thm_deps.ML	Mon Feb 25 19:48:06 2008 +0100
@@ -68,8 +68,8 @@
 
 fun thm_deps thms =
   Present.display_graph
-    (map snd (Symtab.dest (fst
-      (fold make_deps_graph (map Thm.proof_of thms) (Symtab.empty, [])))));
+    (map snd (sort_wrt fst (Symtab.dest (fst
+      (fold make_deps_graph (map Thm.proof_of thms) (Symtab.empty, []))))));
 
 end;