bug#3179: Entering Chinese "zero": add U+3007

[Štěpán Němec]

On Sun, 13 Oct 2019 20:41:17 +0200
Lars Ingebrigtsen wrote:

> jidanni@jidanni.org writes:
>
>> With locale zh_TW.UTF-8 and toggle-input-method, we can type
>> Possible completion and corresponding characters are:
>>  ling2:(1/6) 1.零 2.玲 3.靈 4.鈴 5.齡 6.陵 7.凌 8.菱 9.聆 0.羚...
>>        (6/6) 1.駖 2.蕶 3.爧 4.堎 5.○
>>
>> Useful when one wants to type the year 2003:
>> 公文都有「二○○三年」，非「二零零三年」。
>>
>> But in http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=427519
>> MH> You probably want "〇" (U+3007) instead of "○" (U+25CB)
>> So maybe add that in addition (not instead).
>>
>> (And ０, 0...? nah.)
>
> I know nothing about this, but the suggestion is to use
>
>   name: IDEOGRAPHIC NUMBER ZERO
>
> instead of 
>
>   name: WHITE CIRCLE
>
> I have no idea what that means.  But there's:
>
> (eval-after-load "quail/PY-b5"
>   '(quail-defrule "ling2" ?○ nil t))
>
> which has apparently been in Emacs ever since leim-ext.el was added.

Checking the commit history, the file was originally encoded in iso-2022
and I have no idea what "0!r" in that encoding amounts to, but in any
case, U+3007 is the standard way to write ideographic zero. Various
other similar-looking glyphs (in various encodings) can be found in its
place occasionally[1], but in this day and age I see no reason to
encourage that practice (so I suggest "instead", not "in addition" is
the way to go above).

[1] Cf. e.g. here (in Japanese):
https://hp.vector.co.jp/authors/VA000964/html/zero.htm

-- 
Štěpán (reading, writing and speaking Chinese (also as professional
translator and interpreter) and Japanese)