Re: Have `define-key` return the keymap

[Michael Heerdegen <michael_heerdegen@web.de>]

Tianxiang Xiong <tianxiang.xiong@gmail.com> writes:

> If `define-key` returned the keymap, calls to it could be chained together in
> convenient ways, e.g.
>
> ```
> (thread-first (make-sparse-keymap)
>   (define-key (kbd "a") #'foo)
>   (define-key (kbd "b") #'bar))
> ```

A different solution would be to define something analog to
`thread-first' that substitutes always the first value as first argument
instead of the subsequent return values (in this case, this is always
the same object).

A variant of this approach that works without such a new macro:

#+begin_src emacs-lisp
(defun my-keybinder (map)
  (apply-partially #'define-key map))

(let ((map (make-sparse-keymap)))
  (cl-flet ((define-key (my-keybinder map)))
    (define-key (kbd "a") #'foo)
    (define-key (kbd "b") #'bar)
    map))
#+end_src


Michael.