Consensus Call Tranche 8 (Character Adjustments)

[Martin Duerst]

At 03:20 08/10/16, Patrik F$BgM(Btstr$B‹N(B wrote:
>On 15 okt 2008, at 20.13, Andrew Sullivan wrote:
>
>> On Wed, Oct 15, 2008 at 07:19:40PM +0200, Patrik F$BgM(Btstr$B‹N(B wrote:
>>> Are we trusting one more than the other?
>>>
>>> Do we listen more to more active people on this mailing list than
>>> parties not as active?
>>
>> The only reason I have for responding the way I do is that I
>> understand these responses to be the most consistent with the initial
>> principles from which we start: use the Unicode properties, do
>> everything as much as possible by tables, and introduce as few
>> exceptions as are possible and practical.
>
>Understood. Note that if we look at the proposals eszett and the one  
>from korea, the eszett is an exception, while the korean proposal uses  
>the Unicode properties.

Characterizing the eszett as an exception is correct on one level,
but in my view, it's only an exception because we took the wrong
rules for IDNA2003. And these rules are even more wrong for IDNA 2008.

What IDNA 2003 needed was some kind of case mapping. Unicode provided
two levels of case mapping: a) the simple one-to-one case mappings,
and b) special-casing for cases such as eszett (on top of a).

At the time of IDNA 2003, the mood was: 1) We have to take some
existing tables, we can't construct our own or we'll never finish.
2) Take special-casing, because that's what you would do for search,
and domain name lookup is essentially search.

The problem with this is that 2) isn't exactly true. In search,
you get back original documents, so there are no misspelling
issues. For IDNs, you get back whatever you put in after case
folding, and so you end up with misspellings.

So in my view, we should look at what we get when we remove
special-casing from our rules.

Regards,    Martin.



#-#-#  Martin J. Du"rst, Assoc. Professor, Aoyama Gakuin University
#-#-#  http://www.sw.it.aoyama.ac.jp       mailto:duerst at it.aoyama.ac.jp