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[SG16] Agenda for the 2021-10-20 SG16 telecon

From: Tom Honermann <tom_at_[hidden]>
Date: Tue, 19 Oct 2021 15:32:37 -0400
My apologies for being so late in communicating this agenda for
tomorrow's SG16 telecon.

*Please note that there has been a schedule change.* Tomorrow's telecon
was originally scheduled for 2021-10-27 but was moved forward a week to
avoid conflicts with CppCon. The shared calendar has been updated (which
triggered the sending of new meeting invitations).

SG16 will hold a telecon on Wednesday, October *20th* (not the 27th) at
19:30 UTC (timezone conversion
<https://www.timeanddate.com/worldclock/converter.html?iso=20211020T193000&p1=1440&p2=tz_pdt&p3=tz_mdt&p4=tz_cdt&p5=tz_edt&p6=tz_cest>).

The agenda is:

  * D2071R1: Named universal character escapes
      o Add named escape sequences to /universal-character-name/ so that
        these escape sequences can be used everywhere, not just in
        string literals.
      o Use Unicode rules for matching names rather than requiring exact
        case-sensitive names.
  * P1885R8: Naming Text Encodings to Demystify Them
    <https://wg21.link/p1885r8>
      o Continue discussions of issues raised on the LEWG and SG16
        mailing lists.
      o Prohibit mapping to IANA encodings when CHAR_BIT is not 8?
      o Address special cases for IANA mapping purposes:
          + Is UTF-16 valid for ordinary strings when CHAR_BIT is >= 16?
          + Is UTF-16 valid for wide strings when CHAR_BIT is >= 16 and
            sizeof(wchar_t) is 1?
          + Is the underlying representation of a wide string required
            to match an encoding scheme for the encoding form when
            sizeof(wchar_t) is not 1?
          + Limit mapping of wide strings when sizeof(wchar_t) is not 1
            to other, unknown, and the UCS/UTF variants?

A draft of D2071R1 is not yet available, but is expected to be sent to
the SG16 mailing list later today. That draft will address EWG feedback
from Prague <https://wiki.edg.com/bin/view/Wg21prague/P2071R0-EWG>
except that it will specify relaxed checking of character names for
implementation reasons (the prototype implementation that Corentin did
demonstrated how relaxed checking enables a smaller database of valid
character names).

P1885 is back on the agenda to settle questions that have continued to
be raised on the LEWG and SG16 mailing lists. Corentin indicated intent
to change the encoding querying functions to always return unknown when
CHAR_BIT is not 8; we'll discuss the ramifications of that intent.
Concerns about intended behavior for wide strings continue to be raised,
so we'll discuss and poll various approaches for dealing with them.

Tom.


Received on 2021-10-19 14:32:39