P2071 Named universal character escapes

[wg21bot]

P2071R0 Named universal character escapes (Tom Honermann, Peter Bindels)

[jfbastien]

Please send to EWG when SG16 approves.

[tahonermann]

SG16 in Prague: approved P2071R0 with modifications and suggested options to be polled in EWG. Minutes are available at http://wiki.edg.com/bin/view/Wg21prague/SG16P2071R0.

P2071R0: What is our preferred name matching:

In favor	Name match algorithm
6	Exact match
6	Case-insensitive
4	Full UAX44-LM2

Consensus? Either exact match or case-insensitive.

P2071R0: We should support case-insensitive matching as opposed to exact match?

SF	F	N	A	SA
2	3	2	1	2

Consensus? No

P2071R0: Preferred syntax: (vote for 1)

In favor	Syntax
8	Use "\N{XXX}"
0	Use "\u{XXX}" or "\U{XXX}"

Consensus? Yes

P2071R0: Match name aliases?

SF	F	N	A	SA
8	2	0	0	0

Consensus? Yes

P2071R0: Include support for ISO/IEC 10646 named sequences?

SF	F	N	A	SA
0	0	1	6	1

Consensus? No

P2071R0: Forward to EWG with: no UAX44-LM2 matching, no support for named sequences, use of \N, and no recommendation regarding case-sensitivity.

SF	F	N	A	SA
7	3	0	0	0

Consensus? Yes

Adding the EWG and needs-revision labels.

[jfbastien]

EWG Prague Thursday afternoon:

We’re interested in supporting named universal character escapes.

SF	F	N	A	SA
14	5	0	0	0

This should further support aliases.

SF	F	N	A	SA
18	2	1	0	0

It should further be case insensitive.

SF	F	N	A	SA
0	6	6	9	2

It should further support UAX44-LM2 with arbitrary spaces and dashes.

SF	F	N	A	SA
1	4	5	8	5

The paper is not tentatively ready yet. We want to see the updated paper before marking it as tentatively ready.

[jensmaurer]

This should be seen by SG22, because WG14 might want to do the same thing.

[tahonermann]

SG16 reviewed a draft revision of P2071R1 during its 2021-10-20 telecon. The following polls were conducted.

• Poll 1: We should support both \u{xxxx} and \u(xxxx) (resp. \N{ABCD} and \N(ABCD))
  for better support on EBCDIC systems and others where { and } are not consistently encoded
  in the character sets customarily used for source code.

  • Attendance: 9

    SF	F	N	A	SA
    1	0	2	4	2

  • Consensus against.

• Poll 2: Despite previous EWG feedback, we recommend the use of the UAX44-LM2 name matching algorithm.

  • Attendance: 9

    SF	F	N	A	SA
    1	3	3	1	1

  • No consensus.

  • SA: I want to be able to easily grep for names; most other languages don't support loose matching.

• Poll 3: Named escape sequences should be specified in the language as an alternative form of universal-character-name.

  • Attendance: 9

    SF	F	N	A	SA
    5	3	0	0	0

  • Strong consensus in favor.

[erichkeane]

EWG reviewed 2071R1 at the November 10th, 2021 telecon. The following polls were taken.

EWG would like to see further work to evaluate implementing the functionality of P2071R1 as a library feature.

SF	F	N	A	SA
0	1	2	6	1

Result: Consensus Against

EWG sends P2071R1 to electronic polling with the intent of sending it to CWG for inclusion in C++23.

SF	F	N	A	SA
4	4	0	1	0

Result: Consensus

[wg21bot]

P2071R1 Named universal character escapes (Tom Honermann, Steve Downey, Peter Bindels, Corentin Jabot, R. Martinho Fernandes)

[jensmaurer]

CWG telecon 2022-02-25: Reviewed; needs updates.

[jfbastien]

2022-02 poll results:

SF	F	N	A	SA
12	14	3	3	1
Abstain: 12

Poll outcome:✅ consensus

[jensmaurer]

CWG telecon 2022-03-25: Approved D2071R2 on the condition of adding a note; Jens to check.

[jensmaurer]

The note has been added.

[wg21bot]

P2071R2 Named universal character escapes (Tom Honermann, Steve Downey, Peter Bindels, Corentin Jabot, R. Martinho Fernandes)

[AaronBallman]

This was discussed at the June 2022 SG22 meeting. No polls were taken and no specific concerns were raised. Removing the SG22 tag.