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Re: Rewording wording for named-universal-characters

From: Jens Maurer <Jens.Maurer_at_[hidden]>
Date: Tue, 1 Mar 2022 08:47:57 +0100
On 01/03/2022 01.04, Steve Downey wrote:
> I'll upload a D2071 to the wiki. Jens, do you have a preference about R2 vs R3 for it, since we did review the paper last week?

Keeping R2 is fine.

> Wording:

Italics for named-universal-character , please.
Italics for n-char-sequence, please.

(Both are grammar non-terminals.)

Bullets instead of lone hyphens in the text.


In the note:

"character name alias" should always have "associated"
in front of it, because I guess that's the term of art.


NameAliases.txt should be monospace font.


Jens



> Modify [lex.charset]
>
> (lex.charset.3)The universal-character-name construct provides a way to name other characters.
>
>
> /n-char/: one of
> |A B C D E F G H I J K L M N O P Q R S T U V W X Y Z|
> |0 1 2 3 4 5 6 7 8 9|
> |U+002D HYPHEN-MINUS|
> |U+0020 SPACE|
>
> /n-char-sequence/:
> /n-char/
> /n-char-sequence/ /n-char/
>
> /named-universal-character/:
> |\N| { /n-char-sequence/ }
>
> /hex-quad/:
> /hexadecimal-digit/ /hexadecimal-digit/ /hexadecimal-digit/ /hexadecimal-digit/
>
> /universal-character-name/:
> |\u| /hex-quad/
> |\U| /hex-quad/ /hex-quad/
> /named-universal-character/
>
> A /universal-character-name/ of the form |\u| /hex-quad/ or |\U| /hex-quad/ /hex-quad/ designates the character in the translation character set whose UCS scalar value is the hexadecimal number represented by the sequence of /hexadecimal-digits/ in the /universal-character-name/. The program is ill-formed if that number is not a UCS scalar value.
>
> A universal-character-name that is a named-universal-character designates the character named by its n-char-sequence. A character is so named if the n-char-sequence is equal to - the associated character name or associated character name alias specified in ISO/IEC 10646 subclause “Code charts and lists of character names” or - the control code alias given in Table X.
>
> [Note: The aliases in table X are provided for control characters which otherwise have no associated character name or character name alias. These names are derived from the Unicode Character Database’s NameAliases.txt. For historical reasons, control characters are formally unnamed. – end note]
>
>
> On Sun, Feb 27, 2022 at 3:36 AM Corentin Jabot <corentinjabot_at_[hidden] <mailto:corentinjabot_at_[hidden]>> wrote:
>
>
>
> On Sun, Feb 27, 2022 at 9:24 AM Jens Maurer <Jens.Maurer_at_[hidden] <mailto:Jens.Maurer_at_[hidden]>> wrote:
>
>
> Steve, please make sure to upload your fixed paper to the 2022-03-11 core
> telecon wiki, under the "D" name.
>
> On 26/02/2022 09.42, Corentin Jabot wrote:
> >
> >
> > On Fri, Feb 25, 2022 at 11:33 PM Jens Maurer <Jens.Maurer_at_[hidden] <mailto:Jens.Maurer_at_[hidden]> <mailto:Jens.Maurer_at_[hidden] <mailto:Jens.Maurer_at_[hidden]>>> wrote:
> >
> > On 25/02/2022 23.20, Corentin Jabot wrote:
> > > Can we flip it around?
> > >
> > >
> > > Then the named-universal-character designates the element of the translation character set whose UCS scalar value is equal to the code point of that character.
> > > Otherwise, the program is ill-formed.
> > > [Note: The lists of names and aliases are guaranteed to be disjoint. An n-char sequence will be found in at most one list. --end note]
> >
> > We want to avoid "matches" because it might mean "some fuzzy match" instead of
> > equality.
> >
> > We want to start the paragraph with the same introducer as the preceding one.
> >
> >
> > This is challenging.
> > There are a lot of moving pieces.
> > Can we rewrite the previous paragraph too?
> >
> >
> > If the n-char-sequence of a named-universal-character is exactly equal to either
> > - The name alias of a character as specified in ISO/IEC 10646 clause 34 "Character names list"
> > - The associated name of a character as specified in ISO/IEC 10646 clause 34 "Character names list"
> > - A control code alias of a character as specified in table X
> > Then the named-universal-character designates the code point of that character.
> >
> > A universal-character-name designates the character in the translation character set whose UCS scalar value is:
> > - For a universal-character-name of the form \u hex-quad or \U hex-quad hex-quad, the hexadecimal number represented by the sequence of hexadecimal-digits in the universal-character-name.
> > - For a named-universal-character, the code point it designates.
> >
> > If a universal-character-name does not designate a UCS scalar value, the program is ill-formed.
>
> I think part of the confusion stemmed from the fact that people were looking at an old
> version of the paper, because I hadn't updated the link at the top of the wiki page.
>
> Suggestion:
>
> A universal-character-name that is a named-universal-character designates the
> character named by its n-char-sequence. A character is so named if the
> n-char-sequence is equal to
> - the associated character name or associated character name alias specified in
> ISO/IEC 10646 subclause "Code charts and lists of character names" or
> - the control code alias given in Table X.
> The program is ill-formed if there is no such character.
>
>
> This is great!
>
>
> Jens
>

Received on 2022-03-01 07:48:08