Minutes: MathML Core meeting 11 May

Attendees:

   -

   David Carisle
   -

   Neil Soiffer
   -

   Brian Kardell
   -

   Murray Sargent
   -

   Frédéric Wang
   -

   Bruce Miller
   -

   Patrick Ion

Regrets: Rob Buis

Agenda:
https://github.com/mathml-refresh/mathml/issues/8#issuecomment-626466388



The meeting was recorded:
https://benetech.zoom.us/rec/share/6pJZFJHJ2ExORIX09Gz1YpU_H4bveaa81iccr_pYyU_m7m3F5Vau1hxdc6Ts0wSd
(Access Password: 7R?w3%%l)

Lots of details pasted in below, but most discussion was not minuted.
Mostly just the issue and the resolution. Listen to the recording if you
want more details.

Frédéric’s Admonition

   -

   Important reminder about our CG's message: Make sure that any feature
   that goes in browser specifications (including MathML Core, specs from CSS
   WG, WHATWG's HTML5 spec, specs from ARIA WG) is coordinated with
   implementers and that they are supportive of the proposal. Implementers
   include browsers' DOM/rendering/a11y teams and developers of screen readers.

Operator Dictionary changes
https://mathml-refresh.github.io/mathml-core/#operator-dictionary (scroll
down to the end)

https://mathml-refresh.github.io/mathml-core/#operator-dictionary-compact
(scroll up a bit)
https://mathml-refresh.github.io/mathml-core/#operator-dictionary-categories-values

Remove multi-char operators from operator dictionary, or at least remove
those with more than two characters (#143)

From the issue, here are a list of multi char operators still in the
operator dictionary:

U00021-00021 !!  {'lspace': 1, 'rspace': 0}

U00021-0003D !=  {'lspace': 4, 'rspace': 4}

U00026-00026 &&  {'lspace': 4, 'rspace': 4}

U0002A-0002A **  {'lspace': 1, 'rspace': 1}

U0002A-0003D *=  {'lspace': 4, 'rspace': 4}

U0002B-0002B ++  {'lspace': 0, 'rspace': 0}

U0002B-0003D +=  {'lspace': 4, 'rspace': 4}

U0002D-0002D --  {'lspace': 0, 'rspace': 0}

U0002D-0003D -=  {'lspace': 4, 'rspace': 4}

U0002D-0003E ->  {'lspace': 5, 'rspace': 5}

U0002E-0002E ..  {'lspace': 0, 'rspace': 0}

U0002E-0002E-0002E ...  {'lspace': 0, 'rspace': 0} -- U+2026 is Horizontal
Ellipsis

U0002F-0002F //  {'lspace': 1, 'rspace': 1}

U0002F-0003D /=  {'lspace': 4, 'rspace': 4}

U0003A-0003D :=  {'lspace': 4, 'rspace': 4}

U0003C-0003D <=  {'lspace': 5, 'rspace': 5}

U0003C-0003E <>  {'lspace': 1, 'rspace': 1}

U0003D-0003D ==  {'lspace': 4, 'rspace': 4}

U0003E-0003D >=  {'lspace': 5, 'rspace': 5}

U0007C-0007C ||  {'lspace': 2, 'symmetric': True, 'stretchy': True,
'rspace': 2}

U0007C-0007C ||  {'lspace': 0, 'symmetric': True, 'stretchy': True,
'rspace': 0}

U0007C-0007C ||  {'lspace': 0, 'symmetric': True, 'stretchy': True,
'rspace': 0}

U0007C-0007C-0007C |||  {'lspace': 2, 'symmetric': True, 'stretchy': True,
'rspace': 2} -- U+2980 (TRIPLE VERTICAL BAR DELIMITER)

U0007C-0007C-0007C |||  {'lspace': 0, 'symmetric': True, 'stretchy': True,
'rspace': 0}

U0007C-0007C-0007C |||  {'lspace': 0, 'symmetric': True, 'stretchy': True,
'rspace': 0}

U0223D-00331 ∽̱  {'lspace': 3, 'rspace': 3}

U02242-00338 ≂̸  {'lspace': 5, 'rspace': 5}

U0224E-00338 ≎̸  {'lspace': 5, 'rspace': 5}

U0224F-00338 ≏̸  {'lspace': 5, 'rspace': 5}

U02266-00338 ≦̸  {'lspace': 5, 'rspace': 5}

U0226A-00338 ≪̸  {'lspace': 5, 'rspace': 5}

U0226B-00338 ≫̸  {'lspace': 5, 'rspace': 5}

U0227F-00338 ≿̸  {'lspace': 5, 'rspace': 5}

U02282-020D2 ⊂⃒  {'lspace': 5, 'rspace': 5}

U02283-020D2 ⊃⃒  {'lspace': 5, 'rspace': 5}

U0228F-00338 ⊏̸  {'lspace': 5, 'rspace': 5}

U02290-00338 ⊐̸  {'lspace': 5, 'rspace': 5}

U029CF-00338 ⧏̸  {'lspace': 5, 'rspace': 5}

U029D0-00338 ⧐̸  {'lspace': 5, 'rspace': 5}

U02A7D-00338 ⩽̸  {'lspace': 5, 'rspace': 5}

U02A7E-00338 ⩾̸  {'lspace': 5, 'rspace': 5}

U02AA1-00338 ⪡̸  {'lspace': 5, 'rspace': 5}

U02AA2-00338 ⪢̸  {'lspace': 5, 'rspace': 5}

U02AAF-00338 ⪯̸  {'lspace': 5, 'rspace': 5}

U02AB0-00338 ⪰̸  {'lspace': 5, 'rspace': 5}

U02ADD-00338 ⫝̸  {'lspace': 5, 'rspace': 5}

The later group brings up the issue of normal forms as these are combined
characters that have unicode equivalents -- should we remove all that have
single char equivalents?

https://www.w3.org/TR/xml-entity-names/U00338.html

Resolved: Remove: |||, … is already gone

Resolved: Remove: U0223D-00331 but check to see if there an equivalent in
more modern Unicode

Resolved: Remove U02282-020D2, U02283-020D2 but check for equivalents

Resolved: Remove xxx-3338 and check for combining char that follows -- take
properties from xxx

Keep 2 char ASCII but make spacing more consistent
Remove , √ <https://www.fileformat.info/info/unicode/char/221a/index.htm>, ∛
<https://www.fileformat.info/info/unicode/char/221b/index.htm>, and ∜
<https://www.fileformat.info/info/unicode/char/221c/index.htm> from
operator dictionary

Resolved: Move, √, ∛, and ∜ to not stretchy, 3,0 spacing

ⅅ U+2145prefix0.16666666666666666em0N/A

ⅆ U+2146prefix0.16666666666666666em0N/A

∂ U+2202prefix0.16666666666666666em0N/A

Remove default stretchiness of the following infix operators (#23)

http://www.unicode.org/reports/tr25/tr25-15.pdf section 2.15


   -

   U+2044 'FRACTION SLASH' ⁄ -- used for bevelled fractions,
   -

   U+2215 ‘Division Slash <https://www.compart.com/en/unicode/U+2215>’ ∕
   -

   U+002F ‘Solidus’ /  (not stretchy)
   -

   U+27CB ‘MATHEMATICAL RISING DIAGONAL’ ⟋ (not currently in op dict, along
   with 27CD falling diagonal). Neither appear to be used in a stretchy
   context (double coset spaces), nor from the mention of their AMS symbols
   \diagdown, \diagup)



   -

   Infix U+007C ‘Vertical Line’ |  -- stretchy, symmetric
   -

   U+29F8 big solidus
   -

   ⧹ U+29F9 BIG REVERSE SOLIDUS,
   -

   ⫽ U+2AFD DOUBLE SOLIDUS OPERATOR
   -

   ⫻ U+2AFB TRIPLE SOLIDUS BINARY RELATION
   -

   ⧵ U+29F5 REVERSE SOLIDUS OPERATOR,
   -

   ❘ U+2758 LIGHT VERTICAL BAR,
   -

   \ U+005C REVERSE SOLIDUS,



   -

   ∥ U+2225 PARALLEL TO,
   -

   ∣ U+2223 DIVIDES,

MS: we have mfrac which deals with bevelled.

Resolved: remove symmetric, stretchy from these.

https://github.com/mathml-refresh/xml-entities/pull/23

Make all largeop movablelimits #18

First category is integrals, second all big ops like big product, union,
intersections, …; third category has some integral sign in them.

DC: they should be treated as first category.

Resolved: Change later group of integrals to not have moveable limits

Resolved: Change spacing for all largeops to be the same.