Tables and contextual rule for Katakana middle dot

John C Klensin klensin at
Tue Apr 7 18:41:45 CEST 2009

--On Tuesday, April 07, 2009 07:59 -0700 Mark Davis
<mark at> wrote:

> On what basis?

It is a punctuation character.  It looks enough like a
label-separating period in contexts where middle-dots are not
used that it would likely be mistaken for a period in those
contexts.  Such a mistake is fully as dangerous as a character
that looks like a slash.  If it were possible to live with a
restriction that required at least one Asian-Japanese character
(Hiragana, Katakana, or Kanji) in the label, I'd be ok with it,
although a little nervous.  But, if abc・def and 10・0・0・6
(if one doesn't see the characters, the indicators are U+03FB)
would be valid labels under the only acceptable rule, then I
think the middle dot is at high enough risk of causing harm to
be DISALLOWED entirely.  That saddens me as much as it does

On the other hand, if the reason for this problem is that
Romanji is Japanese, then so, I suppose, is hyphen-minus.  I
would suppose that could be used instead and mapped, as a
presentation issue, to middle dot were appropriate.   Not a
wonderful situation, but maybe better than the alternatives.


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