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Subject: Re: SG16 meeting summary for February 26th, 2020
From: Tom Honermann (tom_at_[hidden])
Date: 2020-03-03 18:32:45


On 3/2/20 2:53 PM, Hubert Tong wrote:
> With respect to Jens's comments as recorded re: P1949 (Identifier syntax):

You are referring to these comments, yes?

- Jens replied that preprocessing-token is distinct and that they get
converted into identifiers, keywords, etc... at a particular translation
phase.
- Jens added that this occurs in translation phase 7 per
[lex.phases]p1.7 and [lex.token]p1. Core language wording should be
added here to state that an identifier shall be in NFC form.

>
> Deferring the NFC restriction to phase 7 would not cover the need to
> match macro and macro parameter names to their corresponding references.

That sounds correct to me; at least for the proposal as written. My
interpretation of the discussion so far has been that there has been no
intent to address naming of macros and macro parameters. This is why I
asked during the telecon if the paper should address (preprocessing)
tokens as well as identifiers.  I tend to think that it should since the
same concerns we have for identifiers seem to apply to preprocessing tokens.

Steve, at a minimum, I think the paper should be updated to discuss
preprocessing tokens and include examples like the following (but better):

#define Á 1  // U+00C1
#if !defined(AÌ€) // U+0041 U+0300
// Evil code here
#endif

#define STR(X) #X
#define XSTR(Á) STR(À)  // U+00C1 for the parameter, U+0041 U+0300 for
the macro value.
const char *p = XSTR(x); // String content is "Á" (U+0041 U+0300), not "x"

Tom.

>
> On Fri, Feb 28, 2020 at 6:34 PM Tom Honermann via SG16
> <sg16_at_[hidden] <mailto:sg16_at_[hidden]>> wrote:
>
> The summary for the SG16 meeting held February 26th, 2020 is now
> available.  For those that attended, please review and suggest
> corrections:
> - https://github.com/sg16-unicode/sg16-meetings#february-26th-2020
>
> The next meeting is scheduled for Wednesday, March 11th, from
> 19:30-21:00 UTC (3:30-5:00pm EDT).  An invitation (from
> invite_at_[hidden] <mailto:invite_at_[hidden]>) has been sent
> to the mailing list and prior attendees.  The draft agenda is:
> - Meet and greet for SG16 and the new Unicode Message Format
> Working Group (MFWG)
>
> For any new attendees: The meetings are video conferences
> conducted via BlueJeans.  If you are planning to attend, please
> test your system by visiting https://bluejeans.com/111 before the
> scheduled meeting time.
>
> Tom.
>
> --
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>



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