Re: text-quoting-style

[Eli Zaretskii <eliz@gnu.org>]

> Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org
> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Fri, 28 Aug 2015 00:54:40 -0700
> 
> Eli Zaretskii wrote:
> >> That should suffice for Alan's preferences, as
> >> >he can run Emacs in an environment where curved quotes aren't displayable, e.g.,
> >> >with LC_ALL=C in the environment.
> > Telling people who don't see the Unicode quotes to run under LC_ALL=C
> > is not a good idea, for at least two reasons:
> >
> >    . on platforms that honor LC_ALL in the environment, it will disable
> >      many useful Emacs features unrelated to the issue at hand
> 
> Can you give an example of such a feature?  I'm not seeing the problem.

Anything that is decoded using locale-coding-system, or the default
values derived from it.  If the real locale is nothing like C, I
expect the result to be strings full of raw bytes.  If the real
locale's codeset is UTF-8, you might get away for a while (because
Emacs generally strives to DTRT with unibyte strings), but with any
other codeset the problem should be immediately clear.  E.g., start
Emacs in that way in such a locale, and then look at exec-path: if
there are any non-ASCII file names there, I expect you to see raw
bytes.

Also, some of the guesswork within detect-coding stuff will do wrong
things.

> In environments that can't handle Unicode, perhaps Emacs disables some other 
> features regardless of text quoting style.  If so, it should be OK to disable 
> curved quote display too.

Sorry, "disable" was not a good choice of words.  I meant "break".

> >    . on platforms that don't honor LC_ALL in the environment (Windows),
> >      it won't have any effect
> 
> My suggestion was meant for Alan's environment

But there are people who use other environments that expressed their
dislike of this change.

> The suggestion wasn't meant for Windows users, where I assume the
> problem is solved in a different way

There's no way I know of to run programs on Windows while setting the
locale to a non-default value for just that program.  The only
possibility I'm aware of is for the program itself to call 'setlocale'
or its low-level Windows equivalents.

So if we want to remove text-quoting-style (I don't think we should),
we should at least provide an Emacs command-line option that would
cause Emacs itself call 'setlocale' at startup to switch to a C
locale.  That would at least be portable, although the problems I
mentioned above with locale-coding-system derived values will still be
there.

The next logical step is to provide an option to turn off only these
quotes.  But that's almost identical to what text-quoting-style
already provides, isn't it?

> and no suggestion is needed.

??? Of course it's needed.  Unless we would like to tell those users
to get lost.