Poll for next WG2 meeting

[Wolfgang Corcoran-Mathe]

Hello all,

Thanks to everyone who attended today's meeting. I'll try to post
the minutes shortly. I'm getting out ahead on the poll for the next
one:

https://terminplaner6.dfn.de/p/ace0d1db22d15c9d0f9094bb5e04c441-1708506

Please fill in your available times.

Thanks,

Wolfgang

--
Wolfgang Corcoran-Mathe <w...@sigwinch.xyz>

[Alaric Snell-Pym]

On 16/04/2026 16:26, Wolfgang Corcoran-Mathe wrote:
> Hello all,
>
> Thanks to everyone who attended today's meeting. I'll try to post
> the minutes shortly. I'm getting out ahead on the poll for the next
> one:
>
> https://terminplaner6.dfn.de/p/ace0d1db22d15c9d0f9094bb5e04c441-1708506

I've already filled it in, but then since found I'm the closest next of
kin to somebody who died alone at home, so at some point over the next
weeks all my plans and schedules will be upended by needing to visit
another city to look for a will / clear a house / organise a funeral /
other paperwork... Hopefully I'll be able to bring my laptop and get
Internet access, but just to warn you, I might be a bit awkward! Sorry!

>
> Wolfgang
>

--
Alaric Snell-Pym (M0KTN neé M7KIT)
http://www.snell-pym.org.uk/alaric/

[Wolfgang Corcoran-Mathe]

Alaric,

On 2026-04-18 12:17 +0100, Alaric Snell-Pym wrote:
> I've already filled it in, but then since found I'm the closest next
> of kin to somebody who died alone at home, so at some point over the
> next weeks all my plans and schedules will be upended by needing to
> visit another city to look for a will / clear a house / organise a
> funeral / other paperwork... Hopefully I'll be able to bring my
> laptop and get Internet access, but just to warn you, I might be a
> bit awkward! Sorry!

Thanks for the update. I'm sorry this has happened and I understand
you'll be busy tracking down a thousand details in the coming weeks.
Would you like the rest of us to come up with an agenda, or select
an acting^2 chair for the next meeting?

--
Wolfgang Corcoran-Mathe <w...@sigwinch.xyz>

[Peter McGoron]

Re. balloting, I have put down some questions that are related to the
drafting of the Valued Fascicle:

https://codeberg.org/scheme/r7rs/wiki/The-Aquamarine-Ballot

Some important things:

1. Decide on what we should ask for uninterned symbols. Explicit library
support? Implicitly allowed like in R7RS-Small? Forbidden? (Maybe we can
ask all three and use ranked-choice voting.)

2. Further Unicode scope questions, as necessary.

3. How much of IEEE arithmetic to require, and if we want to require
flonums to be IEEE binary64. (This would also touch upon requirements
for using the most precise floating point format available, R6RS §3.4
paragraph 5).

-- Peter McGoron

[John Cowan]

On Mon, Apr 20, 2026 at 7:47 PM 'Peter McGoron' via scheme-reports-wg2
<scheme-re...@googlegroups.com> wrote:

> https://codeberg.org/scheme/r7rs/wiki/The-Aquamarine-Ballot

Note to all: the version at this link is much longer than the version
in this email.

I have added "or both" to the question about #u1 syntax vs. #* syntax
for bitvectors, and by adding "or neither" we can eliminate question 1
(but I didn't do that).

> 3. [...] (This would also touch upon requirements

> for using the most precise floating point format available, R6RS §3.4
> paragraph 5).

There are some existing issues concerned with this: #67 (mixed
precision, which I just reopened to add a comment) and #275, which is
about requiring flonums to be binary64 and adding optional
C#-compatible syntax for (optional) decimal floats.

I'll add my views on this ballot in brief:. Bitvector syntax: both.
Mantissa width syntax: yes. Multidimensional array syntax: yes per
SRFI 268, producing a result that is opaque in the Foundations.
Uninterned symbols: no (I see no use cases for them any more).
Unicode scalar values only: yes. Locale support: maybe in the
Batteries. Strict IEEE 754 compliance: yes.

[Wolfgang Corcoran-Mathe]

We have a bunch of poll responses and it looks like next Thursday
(2026-04-30) at 13:00 UTC works for everyone (except perhaps Alaric,
whose schedule has become complicated).

Unless there are objections I'll schedule that as the next meeting
time.

Alaric, if you have a chance, please let us know if you need someone
to handle the agenda & chairing duties.

--
Wolfgang Corcoran-Mathe <w...@sigwinch.xyz>

[Peter McGoron]

On 4/20/26 20:46, John Cowan wrote:
> Mantissa width syntax: yes.

I have some doubts about balloting it now. We would have to modify the
syntax to make the grammar LL(k). If we add the R6RS mantissa width in
combination with escaped identifiers in the way the R7RS describes them,
then you need arbitrary lookahead to disambiguate a mantissa width from
the start of an escaped identifier. Example:

(let ((|111111111| 5))
(cons 5|111111111|))

The only correct parse of this is the one that evaluates to (5 . 5),
which would require the parser to back out of parsing 5 with a very long
mantissa. Another example:

(let ((|abcd| 5))
(cons 5|111111111|abcd|))

this would parse as (5.0|111111111 . 5), but would also require some
tricky parsing to get right.

______________________

I've added many more questions to the proposed ballot:

https://codeberg.org/scheme/r7rs/wiki/The-Aquamarine-Ballot

-- Peter McGoron