Re: [apps-discuss] i18n intro, Sunday 14:00-16:00

Bjoern Hoehrmann <derhoermi@gmx.net> Thu, 21 July 2011 16:56 UTC

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From: Bjoern Hoehrmann <derhoermi@gmx.net>
To: Joe Hildebrand <joe.hildebrand@webex.com>
Date: Thu, 21 Jul 2011 18:57:02 +0200
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Subject: Re: [apps-discuss] i18n intro, Sunday 14:00-16:00
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* Joe Hildebrand wrote:
>The property of NFK?D that we like is that if you have a string of
>codepoints that is already in NFK?D, you can check that the string is in the
>correct normalization form without having to allocate memory.  With NFK?C,
>you'll have to decompose (allocating memory), recompose (at some finite CPU
>cost), then recompose (possibly allocating *again*) just to check if you
>have already done the normalization.

The set of strings that is in Normalization Form C is a regular language
see <http://lists.w3.org/Archives/Public/www-archive/2009Feb/0071.html>,
so recognizing NFC strings is just as easy as recognizing NFD strings if
ignore that automata for NFC are bigger and harder to make than for NFD.
It's easier to use the simple heuristic in the specification and then do
what you suggest above for complicated strings, but it's not necessary.
-- 
Björn Höhrmann · mailto:bjoern@hoehrmann.de · http://bjoern.hoehrmann.de
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