bug#56323: 29.0.50; [v2] Add new customisable phonetic Tamil input method

[Eli Zaretskii <eliz@gnu.org>]

> From: Visuwesh <visuweshm@gmail.com>
> Cc: 56323@debbugs.gnu.org
> Date: Fri, 01 Jul 2022 22:07:38 +0530
> 
> >> BTW, do you have any other code/documentation review?  And what about
> >> the patch I posted in https://lists.gnu.org/archive/html/bug-gnu-emacs/2022-06/msg02256.html?
> >> No rush but I would like to know if it can go in since it only addresses
> >> fallouts from the previous bug in this area.  Thanks.
> >
> > It sounded to me like you are still working on the code, so I didn't
> > see a need to review it.  If you have specific parts that you'd like
> > me to review nonetheless, please tell which parts are those.
> 
> Thanks.  The patch I posted in
> https://lists.gnu.org/archive/html/bug-gnu-emacs/2022-06/msg02256.html
> is done, and can be pushed to master if you see no problems.

I installed it, thanks.

> Also, I would like to know if there's a better to write the :set
> function for the defcustoms tamil-vowel-translation,
> tamil-consonant-translation, tamil-misc-translation, tamil-native-digits
> without the boundp check chain below,
> 
>     (defun tamil--set-variable (sym val)
>       (set-default sym val)
>       (when (and (boundp 'tamil-vowel-translation)
>                  (boundp 'tamil-consonant-translation)
>                  (boundp 'tamil-misc-translation)
>                  (boundp 'tamil-native-digits))
>         (tamil--update-quail-rules)))

Why do you need a single function for all of them?  Would a separate
setter function for each defcustom do the job?

I also don't understand the need for the boundp tests -- the function
will live on the same indian.el file as the defcustoms, so if the
function is defined, the defcustoms are also bound, no?

> I'm also doubtful about the current group being used for these
> defcustoms.  Should I go ahead and make a new 'tamil' group and make it
> a subgroup of leim or i18n?

It's okay to have a separate group, but what would be the subject of
this group?  If it's just about input methods, the name had better
reflected that, and just "tamil" is too general for that.

> And is the prefix tamil- okay or should I change it to something
> else?

I see no problem with 'tamil-'.

> Finally, I'm unsure if "List of input sequences to translate to ..." is
> clear.  I think it sounds a mouthful and there should be a better way to
> put it.  I think "translation rules" is quite nice but I'm afraid that
> it is too Quail specific and might not be well understood.

I have no problem with that wording, but I wonder whether we should
have these defcustoms in the first place.  What are the chances that
some user will want to change the sequences, and why would they want
that?

P.S. Please in the future don't modify the Subject of the messages in
the same bug report: that makes it harder to find related messages at
least when using Rmail.