Re: Smarter M-x that filters on major-mode

[Lars Ingebrigtsen]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> How 'bout
>
>     (declare (M-x-pred EXP))
>
> which turns into
>
>     (define-symbol-prop '[SYM] (lambda () EXP))
>
> so EXP can be (derived-mode-p 'foo-mode) or it can be nil, or ...

I happened onto another possible use here while testing things -- making
commands available after loading some other package.  That is, we
currently have stuff like

(defun gnus-summary-thing ()
  (interactive)
  (require 'thing)
  (do-thing-stuff))

which just signals an error if `thing' doesn't exist.  Instead we could
do something like:

(defun gnus-summary-thing ()
  (interactive)
  (declare (M-x-pred (find-library "thing")))
  (require 'thing)
  (do-thing-stuff))

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no