[UA-discuss] IANA IDN Tables

[Andrew Sullivan]

On Mon, Feb 26, 2018 at 05:30:38PM +0000, Mark Svancarek via UA-discuss wrote:
> コ andム  are katakana characters, so only examples 1 and 3 are valid from a
> language perspective.   Those characters do not exist within hiragana and I do
> not believe they exist as standalone Chinese characters, either.

That doesn't matter, because the characters _below_ the Katakana
_could_ be Han or whatever.  Japanese is written in multiple scripts,
so knowing that one label is only written with Katakana does not tell
you whether another label might have Han characters in it.  It
doesn't, indeed, even tell you that there might not be a Chinese name
lower in the tree, much as com today permits characters outside the
ASCII range.

Best regards,

A

-- 
Andrew Sullivan
ajs at anvilwalrusden.com