Prohibiting mapping of PVALID characters

["Martin J. Dürst"]

On 2009/12/10 6:53, Paul Hoffman wrote:

> draft-ietf-idnabis-protocol-17.txt mentions mapping in only two places.

> 5.2:
>
>     The string is converted from the local character set into Unicode, if
>     it is not already in Unicode.  Depending on local needs, this
>     conversion may involve mapping some characters into other characters
>     as well as coding conversions.  Those issues are discussed in
>     [IDNA2008-Mapping] and the mapping-related sections (Sections 4.4, 6,
>     and 7.3) of [IDNA2008-Rationale].  The result MUST be a Unicode
>     string in NFC form.
>
> The words in 4.1 are quite definitive, irrespective of whether or not the string contains PVALID characters. If you want to add something, it would be in 5.2. A proposed change to the second sentence would be:
>
> Depending on local needs, this conversion may involve coding
> conversions. The conversion may also involve mapping some characters;
> however, such mapping MUST NOT be applied to any character that has a
> type of PVALID, regardless of the local needs.

To fix for Ken's catch, what about (I also eliminated the first sentence 
of Paul's proposal, because it seems to just repeat the general 
statement in the sentence before (which Paul didn't copy)):

 >>>>
The string is converted from the local character set into Unicode, if
it is not already in Unicode.  This conversion may also involve mapping 
some characters or sequences of characters to others. However, such 
mapping MUST be limited to applying NFC for any character that has a
type of PVALID, regardless of the local needs.
 >>>>

Regards,   Martin.

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