Re: detecting encoding for Japanese

[Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Großjohann)]

Katsumi Yamaoka <yamaoka@jpl.org> writes:

>>>>>> In <vaf1y8g5yck.fsf@INBOX.auto.gnus.tok.lucy.cs.uni-dortmund.de>
>>>>>>	Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Großjohann) wrote:
>
> Kai> Another thought: Mule itself also has a priority list of
> Kai> encodings.  So I wonder why does Gnus need another priority list?
> Kai> Normally, I'd guess that Japanese would normally configure their
> Kai> Emacs for the right priorities, and then Gnus should do the right
> Kai> thing automatically.  There could be two reasons why this is not
> Kai> happening: (1) Japanese use a different encoding in email than in
> Kai> editing files, or (2) the priorities that Emacs sets up normally
> Kai> do not propagate properly to Gnus, or (3) Emacs does not set
> Kai> itself up for the right priorities at all when users setup a
> Kai> Japanese language environment.  Yes, I can't count...
>
> That's a good consideration.  (1) is the main reason.  Though
> iso-2022-jp is used for mail messages, euc-jp has mainly been
> used in UNIX and DOS has used shift_jis.  Although it will be
> different with the system-type, Emacs gives a priority to euc-jp
> or shift_jis in general and it is a right way for editing files.
> It seems to be a good way that Emacs offers the priority list
> for mails apart from the list for files for the specified
> language environment.

Okay.  So it seems that Japanese users always want what you are
saying.

What do you think about changing the default value to the following
expression?

    (when (string= current-language-environment "Japanese")
      '(iso-2022-jp iso-2022-jp-2 japanese-shift-jis utf-8))

We could add a comment saying that we still need to investigate which
values are good for other language environments.

But I wonder if there is a right way to do this?  The right way,
IMHO, would be to use the standard coding system priorities in
principle, except that they are slightly modified to prefer
iso-2022-jp over euc-jp.  Hm.  "emacs -q -no-site-file", then setting
the Japanese language environment, tells me:

/----
| Priority order for recognizing coding systems when reading files:
|   1. iso-2022-jp (alias: junet)
|   2. japanese-iso-8bit (alias: euc-japan-1990 euc-japan euc-jp)
|   3. japanese-shift-jis (alias: shift_jis sjis)
|   4. iso-2022-jp-2 
|   5. iso-latin-1 (alias: iso-8859-1 latin-1)
|   6. iso-2022-7bit 
|   7. iso-2022-8bit-ss2 
|   8. emacs-mule 
|   9. raw-text 
|   10. chinese-big5 (alias: big5 cn-big5)
|   11. no-conversion 
|   12. mule-utf-8 (alias: utf-8)
\----

So it seems that Emacs already prefers iso-2022-jp over euc-jp.  It's
not clear to me where the problem comes from.  Do you get a different
output from M-x describe-coding-system RET RET?

kai
-- 
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