Re: translation-table-for-input

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Cc: Kenichi Handa <handa@m17n.org>,  emacs-devel@gnu.org
> Date: Fri, 30 Jan 2009 20:50:50 -0500
> 
> > Compiling simple.el curses thusly:
> >     In quoted-insert:
> >     simple.el:692:22:Warning: `translation-table-for-input' is an obsolete
> > 	variable (as of Emacs 23.1).
> 
> >     In zap-to-char:
> >     simple.el:3150:21:Warning: `translation-table-for-input' is an obsolete
> > 	variable (as of Emacs 23.1).
> >     simple.el:3151:28:Warning: `translation-table-for-input' is an obsolete
> > 	variable (as of Emacs 23.1).
> 
> > I don't think we want to release Emacs 23 with these warnings.  But
> > what should references to `translation-table-for-input' be replaced
> > with?  I looked in etc/NEWS, and all it says is that this variable is
> > obsolete, but doesn't offer any advice about the alternatives.
> 
> This code is part of the implementation of the feature accessible via
> translation-table-for-input, so removing it would amount to removing
> the feature.
> 
> There is no alternative to this feature, BTW.  The only use I've ever
> seen for it, was the char-unification we did in Emacs-22, but in
> Emacs-23 we do this unification differently, which is why it's obsolete.

IIUC, you are saying that translation-table-for-input was only ever
used by Emacs itself.  In that case, there should be no need to mark
this variable as ``obsolete'', since we already got rid of its
obsolete uses in Emacs.  For other uses, this is a useful feature
(according to you), so marking it ``obsolete'' is simply misleading.

> These `obsolete' warnings are a general problem: we have no way to say
> "yes, I know this variable is obsolete, but this is the implementation
> rather than a use of the feature".  The closest we have is
> with-no-warnings, which is a rather blunt tool.

We could say something in the doc string, but what would that be?
``don't use this variable for character unification''?