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Re: Agenda for the 2022-10-12 SG16 telecon​

From: Corentin Jabot <corentinjabot_at_[hidden]>
Date: Fri, 7 Oct 2022 00:19:03 +0200
I would prefer to wait for all nb comments to be filled in. In particular,
US-38 and US-64 may end up conflicting or overlapping with other NB
comments.

Thanks,
Corentin

On Thu, Oct 6, 2022 at 11:59 PM Tom Honermann via SG16 <
sg16_at_[hidden]> wrote:

> SG16 will hold a telecon on Wednesday, October 12th, at 19:30 UTC (timezone
> conversion
> <https://www.timeanddate.com/worldclock/converter.html?iso=20221012T193000&p1=1440&p2=tz_pdt&p3=tz_mdt&p4=tz_cdt&p5=tz_edt&p6=tz_cest>
> ).
>
> The agenda is:
>
> - A presentation by Michael Kuperstein regarding i18n and l10n and
> existing practice in the industry.
> - NB comment processing.
>
> INCITS has made US NB comments available to its members. I reviewed the
> list and identified the following as ones that I believe SG16 should
> establish a position on. There are other comments that are related to
> papers SG16 has previously discussed, but in those cases, I believe the
> concerns raised do not require SG16 input.
>
> Due to duplicated comments in the list of US comments, it is possible that
> the comment identifiers below will change.
> US-2: [defns.multibyte] <http://eel.is/c++draft/defns.multibyte>
>
> The notion of an "execution character set" is no longer given prominence
> in the Draft standard, aside from some notes about its relationship to the
> concept as defined by C, and clarifying that certain character encodings
> are unrelated to this character set. This makes it a questionable choice
> for use in the definition of "multibyte character".
>
> *Proposed change:*
>
> Change the definition of "multibyte character" to use a character encoding
> with a more definite specification given by the Standard.
> US-38: [format.string.escaped]
> <https://eel.is/c++draft/format.string.escaped>
>
> The subject subclause describes how characters or strings are "escaped" to
> be formatted more suitably "for debugging or for logging".
>
> The actual suitability for debugging or for logging depends on the needs
> of the application, and there is a conflict between formatting for human
> readability of the textual content and formatting for clarity and fidelity
> of encoding nuances. Indeed, for the latter, there can still be (for
> stateful encodings) a conflict between formatting for human visual
> inspection versus formatting for machine consumption of the output sequence
> as a C++ string/character literal.
>
> The current design introduces extensions to the API and to the format
> string syntax that assume that there is one specific default that should be
> chosen "for debugging or for logging". The reasoning behind the chosen
> default and the extensibility of the current design does not appear to be
> sufficiently explored.
>
> Note 1:
> An example, for Unicode encodings, of a choice between prioritizing
> between human readability of the textual content and visual clarity of
> encoding nuances is in the treatment of characters having Unicode property
> Grapheme_Extend=Yes. The current design favors visual clarity of encoding
> nuances by outputing such characters as escape sequences.
>
> Note 2:
> For stateful encodings, the lack of return to the initial shift state at
> the end of the sequence cannot be represented using a C++ string/character
> literal unless if a prior shift sequence from the initial shift state is
> rendered via escape sequence(s). It is not clear that scanning forward is
> generally always an option (nor is it clear that doing so is desirable).
>
> *Proposed change:*
>
> Narrow the purported scope and affirm the design choices of the default
> behavior:
> Modify "logging" to "technical logging" and spell out the priorities in
> order in the description (this has the benefit of clearly communicating
> intention and providing guidance for implementation choices).
>
> 1. The output is intended to be a C++ string/character literal that
> reproduces the encoded sequence. (This seems to be taken for granted and
> not made explicit in the current draft.)
> 2. Prefer visually distinguishing between different methods of
> encoding "equivalent" textual content.
>
> Make any adjustments necessary to the API or the format string syntax
> associated with "escaped" strings to allow for future additions for
> alternative escaping.
> US-64: [uaxid.pattern] <https://eel.is/c++draft/uaxid.pattern>
>
> The Unicode org has clarified that the pattern whitespace and pattern
> syntax rules apply to the lexing and parsing of computer languages.
>
> *Proposed change:*
>
> Replace with "UAX#31 describes how formal languages such as computer
> languages should describe and implement their use of whitespace and
> syntactically significant characters during the processes of lexing and
> parsing. C++ does not claim conformance with this requirement."
>
> Tom.
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>

Received on 2022-10-06 22:19:17