* lisp/emacs-lisp/avl-tree.el: New avl-tree-stack datatype. Add new

traversal functions for avl-trees.  Consolidate rebalancing code.

diff --cc lisp/ChangeLog
index 64dd2af,8c40eab..29749a7
--- 1/lisp/ChangeLog
--- 2/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@@ -1,4 -1,32 +1,34 @@@
- 2011-05-27  David Michael  <fedora.dm0@gmail.com>
+ 2009-11-23  Toby Cubitt  <toby-predictive@dr-qubit.org>
+ 
+       * emacs-lisp/avl-tree.el: New avl-tree-stack datatype.  Add new
+       traversal functions for avl-trees.
+       (avl-tree--stack): New struct.
+       (avl-tree-stack-p, avl-tree--stack-repopulate): New funs.
+       (avl-tree-enter): Add optional `updatefun' arg.
 -      (avl-tree--do-enter): Add optional `updatefun' arg.  Change return value.
++      (avl-tree--do-enter): Add optional `updatefun' arg.
++      Change return value.
+       (avl-tree-delete): Add optional `test' and `nilflag' args.
 -      (avl-tree--do-delete): Add `test' and `nilflag' args.  Change return value.
++      (avl-tree--do-delete): Add `test' and `nilflag' args.
++      Change return value.
+       (avl-tree-member): Add optional `nilflag'
+       (avl-tree-member-p): New function.
+       (avl-tree-mapc, avl-tree-mapf, avl-tree-mapcar): New functions.
+       (avl-tree-stack, avl-tree-stack-pop, avl-tree-stack-first)
+       (avl-tree-stack-empty-p): New functions.
+ 
+ 2009-11-23  Toby Cubitt  <toby-predictive@dr-qubit.org>
+ 
+       * emacs-lisp/avl-tree.el (avl-tree--del-balance): Rename from
+       avl-tree--del-balance1 and make it work both ways.
+       (avl-tree--del-balance2): Remove.
+       (avl-tree--enter-balance): Rename from avl-tree--enter-balance1 and
+       make it work both ways.
+       (avl-tree--enter-balance2): Remove.
+       (avl-tree--switch-dir, avl-tree--dir-to-sign, avl-tree--sign-to-dir):
+       New macros.
+       (avl-tree--mapc, avl-tree-map): Add direction argument.
+ 
+ 2011-05-27  David Michael  <fedora.dm0@gmail.com>  (tiny change)
  
        * files.el (interpreter-mode-alist): Add rbash (bug#8745).