Re: Alternative defaults for visually impaired users? (was: [RFC] The best way to choose an "action" at point: context-menu-mode, transient, which-key or embark? (was: Fwd: Org-cite: Replace basic follow-processor with transient menu?))

[Ihor Radchenko <yantar92@posteo.net>]

Eli Zaretskii <eliz@gnu.org> writes:

>> ... I meant support and maintenance in Emacs
>> core. IMHO, these features are too important for third-party package that
>> might be abandoned.
>> ... 
>
> We do want to have accessibility features in Emacs, if that is what
> you are asking.  (In some cases we already do: e.g., see the
> Windows-specific variable w32-use-visible-system-caret, which aims
> specifically at aiding screen-reading software.)

Thanks for the clarification. Then, let me expand on the idea I have.

I imagine adding "alternative" default value to `defcustom':

(defcustom variable default-value
  :alt-default
    (("blind" . value2)
     ("large-fonts" . value3))
  ...)

Then, consider custom options like

(defcustom accessibility-blind nil
 "When non-nil, Emacs will use defaults suitable for blind users.")
(defcustom accessibility-large-fonts nil
 "When non-nil, Emacs will use defaults suitable for large font sizes.")

If any of the above options is non-nil, and custom variable has its
default value (not changed by user explicitly), instead of
"default-value" a suitable alternative value is used.

Third-party packages will also be able to make use of this semantics,
providing better defaults if necessary.

Elisp manual should also encourage package authors to keep these
alternatives in mind.

WDYT?

-- 
Ihor Radchenko // yantar92,
Org mode maintainer,
Learn more about Org mode at <https://orgmode.org/>.
Support Org development at <https://liberapay.com/org-mode>,
or support my work at <https://liberapay.com/yantar92>