From: Ulrich Mueller <ulm@gentoo.org>
To: Eli Zaretskii <eliz@gnu.org>
Cc: emacs-devel@gnu.org
Subject: Re: Coding systems vietnamese-vscii and vietnamese-tcvn
Date: Fri, 28 Jul 2023 20:03:10 +0200 [thread overview]
Message-ID: <u8razkj6p@gentoo.org> (raw)
In-Reply-To: <83jzutbeim.fsf@gnu.org> (Eli Zaretskii's message of "Fri, 21 Jul 2023 16:06:09 +0300")
>>>>> On Fri, 21 Jul 2023, Eli Zaretskii wrote:
>> From: Ulrich Mueller <ulm@gentoo.org>
>> Cc: emacs-devel@gnu.org
>> Date: Fri, 21 Jul 2023 14:52:55 +0200
>>
>> >>>>> On Fri, 21 Jul 2023, Eli Zaretskii wrote:
>>
>> > Why is the fact that we have two separate coding systems a problem in
>> > this case?
>>
>> Presumably it works fine as-is, but is there any benefit of having such
>> duplication?
> I cannot see any clear benefits either way.
> Maybe we need to ask Vietnamese users. The comments in
> lisp/language/vietnamese.el say that vscii is deprecated.
I have asked a Vietnamese speaker. Paraphrasing their answer: VSCII is
the encoding described in standard TCVN 5712:1993. The terms can be used
interchangeably; there is no reason to have separate character tables.
So the statement in the Vietnamese language info that "VSCII is
deprecated in favor of TCVN-5712" doesn't appear to be correct; the two
terms are synonyms for the same encoding.
I also looked up the original standard. TCVN 5712:1993 defines two
encodings which it names VN1 (aka VSCII-1) and VN2 (aka VSCII-2).
VSCII-2 (VN2) defines these code points:
- 0x00 to 0x7f are identical to ASCII,
- 0x80 to 0x9f are the C1 controls,
- 0xa0 to 0xff contain 96 non-ASCII characters.
VSCII-1 (VN1) is different from VSCII-2 in that it also replaces code
points 0x01-0x02, 0x04-0x06, 0x11-0x17, and 0x80-0x9f by 44 additional
non-ASCII characters, for a total of 140 non-ASCII characters.
There is also an updated standard TCVN 5712:1999 which mentions only one
encoding identical to VSCII-1, i.e. VSCII-2 is no longer part of this
later version of the standard.
So I suggest to define only coding system vietnamese-vscii, and make
vietnamese-tcvn an alias of it. If this a acceptable, I can prepare a
patch for lisp/language/vietnamese.el.
next prev parent reply other threads:[~2023-07-28 18:03 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-21 11:26 Coding systems vietnamese-vscii and vietnamese-tcvn Ulrich Mueller
2023-07-21 12:34 ` Eli Zaretskii
2023-07-21 12:52 ` Ulrich Mueller
2023-07-21 13:06 ` Eli Zaretskii
2023-07-28 18:03 ` Ulrich Mueller [this message]
2023-07-28 18:53 ` Eli Zaretskii
2023-07-29 5:19 ` Ulrich Müller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=u8razkj6p@gentoo.org \
--to=ulm@gentoo.org \
--cc=eliz@gnu.org \
--cc=emacs-devel@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.