Minutes: MathML Full meeting 24 October, 2024

 Attendees:

   - Neil Soiffer
   - Louis Maher
   - David Carlisle
   - Bruce Miller
   - Deyan Ginev
   - Murray Sargent
   - Moritz Schubotz
   - David Farmer

<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-regrets>
Regrets
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-action-items>Action
Items

*CONSENSUS* NS asked if when speaking expressions involving the term
divergence or curl if the word "of" should be used. For example, the div of
f or the divergence of f or curl of f. The consensus was that the word 'of'
should be used.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0--a-href-https-github-com-w3c-mathml-docs-pull-72-add-quot-structure-quot-property-to-core-properties-list-72-a->Add
"structure" property to core properties list #72
<https://github.com/w3c/mathml-docs/pull/72>

*CONSENSUS* We will add the "literal" (and not structure) property to the
core list.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0--a-href-https-github-com-w3c-mathml-docs-commit-4d7078220cf7ab575129c374ae39cf6a476af40a-intent-concepts-what-notation-to-use-for-number-of-arguments-a->Intent
Concepts: what notation to use for number of arguments?
<https://github.com/w3c/mathml-docs/commit/4d7078220cf7ab575129c374ae39cf6a476af40a>

*VOTE RESULTS* We will use "greater than or equal to" to indicate variable
arity. Use a single character for this.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0--a-href-https-github-com-w3c-mathml-pull-511-discussion-about-update-for-describing-matching-concepts-a->Discussion
about update for describing matching concepts
<https://github.com/w3c/mathml/pull/511>

*ACTION* BM will rewrite chapter 5 of the spec, and DG will review it.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-agenda>
Agenda
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-1-announcements-updates-progress-reports>1.
Announcements/Updates/Progress reports

*CONSENSUS* NS asked if when speaking expressions involving the term
divergence or curl if the word "of" should be used. For example, the div of
f or the divergence of f or curl of f. The consensus was that the word 'of'
should be used.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-spec-updates>spec
updates
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-action-item-updates>action
item updates

DC: Well, I had some action items which I knocked off, which were mostly
commenting in various issues, which will probably come up when you come to
the issues.

DC and BB: we can't write a CSS rule that would change the spacing around
specific operators.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-0-2-mathml-4-issues->2.
MathML 4 issues:
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-1--a-href-https-github-com-w3c-mathml-docs-pull-72-add-quot-structure-quot-property-to-core-properties-list-72-a->Add
"structure" property to core properties list #72
<https://github.com/w3c/mathml-docs/pull/72>

("literal" or "structure")

NS was going to add the "structure" property to the core properties When DG
pointed out that we had changed the name of the property from structure to
literal. NS wanted to see if we still had this view.

MUS said that the word ”literal" implies that you read what is there and
not interpret it.

*CONSENSUS* We will add the "literal" (and not structure) property to the
core list.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-1--a-href-https-github-com-w3c-mathml-docs-commit-4d7078220cf7ab575129c374ae39cf6a476af40a-intent-concepts-what-notation-to-use-for-number-of-arguments-a->Intent
Concepts: what notation to use for number of arguments?
<https://github.com/w3c/mathml-docs/commit/4d7078220cf7ab575129c374ae39cf6a476af40a>

NS: We are discussing what notation to use to indicate the presence of two
or more arguments in a concept. Originally we used a "*" (star) for this
symbol.

BM said to use 1+ (plus) where + indicates more arguments may be possible.

DC suggested greater than or equal to. Use the greater than or equal to
sign for this.

DG: I'd stick to standard's syntax and not invent anything here.

NS: There is a standard for a regular expression Indicating the number of
arguments.

NS: Should we use regular expression grammar like curly braces?

DC: It is OK to use a fixed number. For power, you would use a "2".

BM: It effectively means that power with four arguments is an unknown
concept as opposed to one with two arguments. In the unknown case, the
system can do whatever it wants.

From Moritz Schubotz to everyone: So, we write 1 or [1,∞] This is by the
way https://en.wikipedia.org/wiki/ISO_31-11

We discussed how to indicate the situation when there was a lower limit and
an upper limit on the number of arguments.

DG: Greater than or less than could be used. You can cap the number of
arguments from both sides.

DC: Did not see a case where you would have to give a number range for the
number of arguments.

From Murray Sargent to everyone: Variable number is often indicated by ...

From Moritz Schubotz to everyone: see
https://en.wikipedia.org/wiki/Variadic_function

DG: The summary of my position is that between the plus character and the
greater than character, I prefer the greater than character.

DG: The argument number could be auto generated from the speech hints.

NS: The speech hints with stars in them could be difficult to process.

DG: This is just a lack of having a convention. There's no particular
difficulty involved. Just introduce a convention.

MuS: I've been using Markdown a lot recently. When you use less than sign
or greater than sign, it messes up HTML. You have to use the equivalent
numbers for the less than and greater than signs.

DC: This is not an issue in YAML.

From Murray Sargent to everyone: ≥ is U+2265

DC: I don't think we should generate the arity from the speech hints
because the reality Of the name and of the property is what you are
matching against.

DC: We should control the contents of the first three columns of the table
(Concept, Arity, and Property). The speech hints are subjective, and we do
not have to follow them.

DC: Why parse the speech hints when you do not have to do it.

DG: The speech hints indicate the order of the arguments.

DC: Different languages could have different concerns.

From Murray Sargent to everyone: For max or min, I'd use ≥2

*VOTE RESULTS* We will use "greater than or equal to" to indicate variable
arities. Use a single character for this.
<https://sandbox.cryptpad.info/code/inner.html?ver=2024.9.0-5-migration2#cp-md-1--a-href-https-github-com-w3c-mathml-pull-511-discussion-about-update-for-describing-matching-concepts-a->Discussion
about update for describing matching concepts
<https://github.com/w3c/mathml/pull/511>

NS: We had a pull request for this a year ago.

BM suggested rewriting chapter 5.

*ACTION* BM will rewrite chapter 5 of the spec, and DG will review it.

NS: The match depended on the normalized name, fixity property, and the
number of arguments.