Re: Any infrastructure to select one of a few options in Emacs core?

[Marcin Borkowski <mbork@mbork.pl>]

On 2016-05-09, at 20:16, Drew Adams <drew.adams@oracle.com> wrote:

>> (ask-user-for-option "What would you like to eat?" '("spam" "ham" "eggs"))
>
> So this has nothing to do with Emacs _options_.
>
> You are asking how to present some choices to a user for
> selection.

Yes, sorry for the confusion.

I went with this code:

--8<---------------cut here---------------start------------->8---
(defun select-choice (message choices)
  "Display a buffer with MESSAGE and then CHOICES.
Each element of CHOICES should be a cons cell, whose car is the
result and the cdr is the description.  The user may select one
by pressing a digit."
  ;; TODO: This function is way too simple and not fool-proof!
  (if (> (length choices) 9)
      (error "Too many choices!")
    (save-window-excursion
      (pop-to-buffer " *amsrefs doi selection*" t t)
      (delete-other-windows)		; TODO: this should be fixed
      (erase-buffer)
      (insert message "\n\n")
      (let ((i 0))
	(dolist (choice choices)
	  (setq i (1+ i))
	  (insert (format "%d. %s\n\n" i (cdr choice)))))
      (let ((key (read-key)))
	(if (<= 49 key 57)
	    (car (nth (- key 49) choices))
	  (error "Wrong key pressed!"))))))
--8<---------------cut here---------------end--------------->8---

As it is said in the comment, it is far from ideal, but the whole
program I've been writing for my friend is one big quick hack, so
I didn't bother too much.

Still, it would be really nice if Emacs offered a canonical (and
configurable) way to do things like that.

Best,

-- 
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Faculty of Mathematics and Computer Science
Adam Mickiewicz University