bug#22683: 25.1.50; auto-composition-mode

[Stefan Kangas <stefan@marxist.se>]

Richard Stallman <rms@gnu.org> writes:

> The doc string of auto-composition-mode says:
>
> ======================================================================
> With a prefix argument ARG, enable Auto Composition mode if ARG
> is positive, and disable it otherwise.  If called from Lisp,
> enable the mode if ARG is omitted or nil.
> ======================================================================
>
> The doc string suggests (but does not clearly say) that ARG present
> and non-nil disables the mode.
>
> In fact, using M-:, (auto-composition-mode t) enables the mode.
> (auto-composition-mode 0) disables the mode.
> (auto-composition-mode 1) enables it.
>
> It seems this calls for a doc string fix, or a code fix.

This text was recently changed in response to Bug#49843:

    https://debbugs.gnu.org/cgi/bugreport.cgi?bug=49843

The text now says now says:

,----
| This is a minor mode.  If called interactively, toggle the
| ‘Auto-Composition mode’ mode.  If the prefix argument is positive,
| enable the mode, and if it is zero or negative, disable the mode.
|
| If called from Lisp, toggle the mode if ARG is ‘toggle’.  Enable the
| mode if ARG is nil, omitted, or is a positive number.  Disable the
| mode if ARG is a negative number.
`----

Is that sufficiently clear?

It doesn't say what happens if ARG is zero, so perhaps the last sentence
above should be amended to say "negative number or zero".