[art] Re: Artart early partial review of draft-bray-unichars-09

[Rob Sayre <[e-mail]>]

On Thu, Oct 24, 2024 at 11:59 AM Dale R. Worley <[e-mail]> wrote:

> Rob Sayre <[e-mail]> writes:
> > I think it can be flipped around a bit more:
> >
> > In particular, well-formed UTF-8 cannot represent a surrogate.
>
> I haven't thought through how to implement this.
>
> But I would say the first requirement on the text is that it's clear to
> the previously-uninitiated.
>

[...]


> A good solution is wording which fulfills both requirements.  Finding a
> good solution is much like any other protocol design task in the face of
> conflicting requirements.
>

Hmm, we could expand and give it a citation.

"In particular, well-formed UTF-8 cannot represent a surrogate. See [RFC
3629 / STD 63], Section 3."

There, the reader can find a lengthy explanation that needn't be repeated
in this document.

   "The definition of UTF-8 prohibits encoding character numbers between
   U+D800 and U+DFFF, which are reserved for use with the UTF-16
   encoding form (as surrogate pairs) and do not directly represent
   characters.  When encoding in UTF-8 from UTF-16 data, it is necessary
   to first decode the UTF-16 data to obtain character numbers, which
   are then encoded in UTF-8 as described above."

The term "well-formed" in [UNICODE] is defined in D80-D85, but I'm not sure
this document needs to define that term.

thanks,
Rob