Re: [idn] call for comments for REORDERING

["Mark Davis" <mark@macchiato.com>]

1. Yes, the mapping tables for (1) were singular mappings, so it was not
possible to add the fillers. I agree that ideally the decomposition could
have included fillers -- and that might have been a better choice in
retrospect-- but the compatibility mappings are intended to preserve
fundamental character identity, not formatting -- including whether the jamo
are grouped into a single box in display or not.

Some time ago I asked whether there were any cases where it was absolutely
necessary to have two different IDNs, one with a syllable and the other with
two separate Jamo. Nobody responded with any examples. If you have some,
that would be productive.

2. Martin wrote a very nice response on this, so I won't add anything.

Mark
—————

Δός μοι ποῦ στῶ, καὶ κινῶ τὴν γῆν — Ἀρχιμήδης
[http://www.macchiato.com]

----- Original Message -----
From: "Soobok Lee" <lsb@postel.co.kr>
To: "Mark Davis" <mark@macchiato.com>; "Karlsson Kent - keka" <keka@im.se>;
<idn@ops.ietf.org>
Cc: "Martin Duerst" <duerst@w3.org>; <DougEwell2@cs.com>
Sent: Monday, October 22, 2001 21:06
Subject: Re: [idn] call for comments for REORDERING



----- Original Message -----
From: "Mark Davis" <mark@macchiato.com>
To: "Soobok Lee" <lsb@postel.co.kr>; "Karlsson Kent - keka" <keka@im.se>;
<idn@ops.ietf.org>
Cc: "Martin Duerst" <duerst@w3.org>; <DougEwell2@cs.com>
Sent: Tuesday, October 23, 2001 12:39 PM
Subject: Re: [idn] call for comments for REORDERING


> 1. The compatibility hangul jamo are not the preferred way to express
> isolated jamo in Unicode. That would be by the use of conjoining jamo with
> fillers. If the preferred forms are used, there are no problems.
>
But, KSC5601-->Unicode mapping tables  maps  KSC5601 isolated hangul jamo
into compat hangul jamo. The mapping table was issued by UTC itself and
placed into WIN98,2K,XP and most unix and linux platforms.
Inconsistency!


> 2. NFC does not combine ancient Hangul into syllables because there are no
> syllables that have ancient Hangul in them. It does combine as many modern
> Jamo as possible into syllables. That does not -- at all -- prevent the
use
> of NFC with ancient Hangul.

Rendering problem remains unsolved.
"hangul  syllable ga + old jamo bansioth " != "old hangul syllable
ga+bansioth".
There is defined no such false equivalence  in UTR15.
 Why rendering engine vendors should  make such false workarounds not
recommended in UTC standards?
NFC is  dangerous for ancient hangul.

>
> Mark
> —————
>
> Δός μοι ποῦ στῶ, καὶ κινῶ τὴν γῆν — Ἀρχιμήδης
> [http://www.macchiato.com]
>
> ----- Original Message -----
> From: "Soobok Lee" <lsb@postel.co.kr>
> To: "Karlsson Kent - keka" <keka@im.se>; <idn@ops.ietf.org>
> Cc: "Martin Duerst" <duerst@w3.org>; <DougEwell2@cs.com>
> Sent: Monday, October 22, 2001 11:40
> Subject: Re: [idn] call for comments for REORDERING
>
>
>
> ----- Original Message -----
> From: "Karlsson Kent - keka" <keka@im.se>
> >
> > > I know current NFC/NFKC has *severely flawed* hangul jamo
> >
> > Now that's a new complaint.  At least to me.  Not even the
> > delegations from DPRK complain about that. (And they have
> > all sorts of complaints.)  Do you care to say a little bit
> > more about what you mean?  Or are we just to take your word
> > for it?  There was a problem in earlier drafts of UAX 15
> > concerning Hangul and NFKC (Hangul syllables were not preserved),
> > but that problem was removed before that UTR became a UAX.
>
> two problems:
>
>  1) NFKC maps   compatibility hangul jamo (U+32??) into
>                 conjoining hangul jamo without fillers.
>     That converts compat hangul jamo sequences into conjoining
>       jamo sequences and they are combined partially in some cases
>         by the NFC following  compatibilty decomposition.
>     Modern hangul informal texts contains compatibiilty jamos very often.
>     If the texts contains choseong + jungseong sequence in compat jamo,
>        they will be affected by this fault.
>     This fault was found by Soobok Lee, too lately.
>
>  2) NFC  does not combine  archaic(old) hangul trailing jamo into the
>      preceding half-combined syllable (from choseong jamo + jungseong
jamo),
>       but leave it alone as an isolated conjoining jamo.
>     That means archail hangul syllable which has old hangul trailing jamo
>       cannot be preserved through out NFKC.
>     NFKC cannot be used for scholarly texts which contains archail hangul
>       syllables.  This fault was found by Martin, too lately.
>
> Mark and Martin knew and told me why this happened.
> Martin, would you comment on this?
>
> Soobok Lee
>
>
> >
> > > I hope UTC cures this BUGGY NFC/NFKC jamo handling as an
> > > exceptional case while it is in  strict adherence to UTR's backward
> > > compatiblity policy & promise.
> >
> > The normal forms for strings of already allocated characters
> > will not be changed any more.
> >
> > Kind regards
> > /Kent K
> >
>
>
>
>