Re: [art] Modern Network Unicode — –02 submitted

Carsten and Peter,

Citing a corrigendum for Unicode 7 at this point is probably a
bad idea.  If you need a reference or more explanation for this,
see Section 23.7 of Unicode 11.0 (same section number in Unicode
10; I haven't taken the time to change Unicode 12).  That new
section is also more complete than the text Peter cites.

best,
    john

--On Monday, July 8, 2019 21:14 -0400 Peter Occil
<poccil14@gmail.com> wrote:

> Saying U+FFFE and U+FFFF (or any other noncharacters) "MUST
> NOT be used" merely "as per the Unicode specification"
> ought to be guided by looking at what the intent of Unicode
> actually is.
> 
> See corrigendum 9 of the Unicode Standard for that intent:
> http://www.unicode.org/versions/corrigendum9.html
> 
> "Noncharacters in the Unicode Standard are intended for
> internal use and have no standard interpretation when
> exchanged outside the context of internal use. However, they
> are not illegal in interchange nor do they cause ill-formed
> Unicode text. This has always been the intent of the standard,
> as expressed by the Unicode Technical Committee."
> 
> Since noncharacters have no standard meaning outside of
> internal use, however, they may be even more problematic than
> the Unicode paragraph and line separators (which do have
> standard meaning but are forbidden in the draft for Modern
> Network Unicode).  Many kinds of protocol strings, such as
> URIs, IRIs, and strings complying with the PRECIS framework,
> do not allow noncharacter code points, while other kinds of
> UTF-8 text, such as JSON, do allow noncharacters.  XML allows
> all noncharacters except for U+FFFE and U+FFFF.
> 
> --Peter
> 
> From: Carsten Bormann
> Sent: Monday, July 8, 2019 4:24 PM
> To: Manger, James
> Cc: art@ietf.org
> Subject: Re: [art]Modern Network Unicode — –02 submitted
> 
> Hi James, Tim, Martin,
> 
> thank you for the quick feedback!  As suggested, I have
> started turning this into a standalone document (of course,
> still requiring RFC 3629, the UTF-8 definition):
> 
> Status:
> https://datatracker.ietf.org/doc/draft-bormann-dispatch-modern
> -network-unicode/ Htmlized:
> https://tools.ietf.org/html/draft-bormann-dispatch-modern-netw
> ork-unicode-02 Diff:
> https://tools.ietf.org/rfcdiff?url2=draft-bormann-dispatch-mod
> ern-network-unicode-02
> 
> I hope I haven't missed anything important from RFC 5198
> that I wanted to keep.   Maybe time to involve the authors of
> that RFC…
> 
> Grüße, Carsten
> 
> 
>> On Jul 8, 2019, at 04:18, Manger, James
>> <James.H.Manger@team.telstra.com> wrote:
>> 
>> Would be nicer if it wasn't written as a diff from RFC5198
>> (Network Unicode). That is, if you could get all the rules
>> directly from this doc. For instance, I assume Clean Modern
>> Network Unicode must/should be NFC. Keep the RFC5198
>> comparisons for an informative annex.
> 
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