Re: master 40dcf9c2ab 4/5: read-multiple-choice: Display "SPC" instead of " "

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Sun, 26 Dec 2021 09:09:15 -0800
> Cc: emacs-devel@gnu.org
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I don't think I like the result of this changeset.  Now SPC is
> > displayed as [SPC], in brackets, for a reason I cannot understand.
> 
> Before this change, SPC in `read-multiple-choice' was displayed as, for
> example
> 
>     yes; use once
>         ^
> 
> Where the indicated space character was underlined.  So this is
> much less confusing, I think.  (See below regarding the brackets.)

I;m not against using "SPC", I only don't like the brackets around it
(and around "!" as well).  They distract and confuse, IMO.

> Though when moving `disabled-command' to use `read-multiple-choice' it
> is true that we did lose the explanation in the old prompt that said:
> 
>     Type y, n, ! or SPC (the space bar):
> 
> I'm not sure what, if anything we should do about this.  One idea is to
> explain what SPC means at the bottom of the *Disabled Command* buffer.

Why not allow read-multiple-choice to specify longer strings?  It
already does, with "yes" and "no", doesn't it?

> (Personally, I think by the time you stumble upon `disabled-command' you
> should already be proficient enough to know what SPC means.

No, we need to support the case where the user type "C-n n" by
mistake.

> > Why is it a good idea to show some of the responses in brackets?  I
> > say let's remove the brackets altogether, they are not needed,
> > especially since the keys are already in a special face.  Too many
> > features at once are not necessarily a Good Thing.
> 
> I think you have a point regarding these brackets, but note that they
> have always been there with `read-multiple-choice'.
> 
> We could remove them, I think, but would they still be needed on
> terminals that can't display underline?  Or should we perhaps just use
> help-key-binding in that case?

I think having the keys/responses in a special face, even if it's
without the underline, should be enough.  The face should provide
alternatives for the underline, such as distinct colors.