avltree => avl-tree (from jdee-devel)

[Lennart Borgman (gmail)]

There is a discussion on jdee-devel on how to manage the transition from
elib's avltree to avl-tree in current CVS Emacs, see below

Can someone please comment on this?


------- from jdee-devel:

  CK> Can we define avl-tree-* functions if they do not already exist? My
  CK> elisp is atrocious, but in Common Lisp I envision something like:

Sure. There's a old hack out there to make "defcustom" work even when
custom.el isn't available.


  CK> (handler-case (symbol-function 'avl-tree-something)
  CK>   (undefined-function ()
  CK>     (setf (symbol-function 'avl-tree-something) (symbol-function
  CK>     'avltree-something))))

  CK> We could have a bunch of these as top-level forms (one for each
  CK> avl-tree-* function we need to use). They would detect if
  CK> #'avl-tree-something is undefined, and if so, define it to be the same
  CK> function as #'avltree-something.

Something like this might work....


(if (not (require 'avl-tree nil t))
    (progn (require avltree)
           (defalias avl-tree-enter 'avltree-enter)
           (defalias avl-tree-delete 'avltree-delete)
           ....
           ))