Re: Usage of standard-display-table in MSDOS

[Kenichi Handa <handa@m17n.org>]

In article <83y6brkxqe.fsf@gnu.org>, Eli Zaretskii <eliz@gnu.org> writes:

> > From: Kenichi Handa <handa@m17n.org> > Cc:
> emacs-devel@gnu.org > Date: Sat, 28 Aug 2010 13:18:02
> +0900
> > 
> > In article <837hjcm9cw.fsf@gnu.org>, Eli Zaretskii
> <eliz@gnu.org> writes:
> > 
> > > > > "Display characters in the range L to H
> literally."
> > > > 
> > > > > The "literally" part is no longer true, is it?
> > > > 
> > > > What's the meaning of "literally" when a display
> table > > > element is [#xA0]?
> > 
> > > It means that a literal byte 0xA0 is sent to the
> terminal.
> > 
> > From which document, can we get that interpretation?

> That's my understanding of the word "literally".

But, how do you apply that understanding to this element:
  [#x100]

> Plus,
> standard-display-8bit worked like that in previous
> versions of Emacs.  If we mean for it to do something
> else, we should amend the docstring.

The current behaviour of standard-display-8bit is the
natural consequence of the fact that we changed character
codes.  But, perhaps we should explain what "literally"
really means.

> > (aset standard-display-table (unibyte-char-to-multibyte
> #xA0) > (vector (unibyte-char-to-multibyte #xA0)))

> Shouldn't standard-display-8bit be modified to use this, instead of
> what it does now?  It seems like it was previously used to work around
> the terminal encoding, but that fire escape was plumbed in Emacs 23.
> Perhaps we should reinstate that feature?

Yes.  That's why I wrote:

handa> Should we change the above code and all other codes setting
handa> 0x80th..0xA0th elements of a display table?

eliz> Yes.  IMO, we should consistently use the codepoints of eight-bit
eliz> characters in all char-tables.

handa>Ok, if Yidong and Stefan agree too, I'll work on it.

I have not yet got any response but have started the work.

> And there's still the question of what to do with the
> fragment in standard-display-european-internal that uses
> standard-display-8bit.  Should it be removed, or should it
> be rewritten in some way?

The docstring of standard-display-european says it's
semi-obsolete.  But, as far as we provide that function, we
should modify the current code to do what expected.

---
Kenichi Handa
handa@m17n.org