QT4 CG Meeting 156 Minutes 2026-03-10

Regrets: DB, NW

• [ ] David J Birnbaum (DB)
• [X] Reece Dunn (RD)
• [X] Christian Grün (CG)
• [X] Joel Kalvesmaki (JK) Chair.
• [X] Michael Kay (MK)
• [X] Juri Leino (JLO)
• [X] John Lumley (JWL) Scribe
• [X] Alan Painter (AP
• [X] Wendell Piez (WP)
• [ ] Norm Tovey-Walsh (NW)

NW thanks JK and JWL. Assume any errors introduced in the minutes are NW’s fault.

Proposal: Accept the agenda.

Accepted.

Proposal: Accept the minutes of the previous meeting.

Accepted.

The next meeting is planned for 24 March 2026.

Note: Daylight Saving Time begins in North America on Sunday, 8 March. It does not begin in the UK and Europe until Sunday, 29 March. The QT4CG meets on UK and European civil time. The meeting of 24 March will be one hour later in North America.

• [ ] QT4CG-143-02: MK to try to recover the ability to extract formal equivalences into tests
• [X] QT4CG-143-03: JK to look for C14N test suites.
• [ ] QT4CG-144-01: MK to consider if any now lost value comparisons should be added as examples.
• [ ] QT4CG-150-01: NW to ask Jirka for a room at XML Prague for Tuesday/Wednesday
• [ ] QT4CG-150-04: NW to see about a status update on PR #2345; possibly schedule discussion
• [X] QT4CG-151-01: MK to fix the typo in the build-dateTime function.
• [X] QT4CG-152-01: MK to add a note about the new and old syntax for names in PR #2446
• [X] QT4CG-153-01: MK to investigate the indentation problem.
• [X] QT4CG-153-02: MK to turn my suggestions on #1949 into a PR.
  • Close with no action; #1949 remains open
• [X] QT4CG-154-01: MK to review why anyAtomicType didn’t, in fact, become a square box!
• [X] QT4CG-154-02: MK to add a note about “tunneling” package parameters.
• [X] QT4CG-155-01: MK to add an example of function coercion that uses ?.
• [X] QT4CG-155-02: MK to clarify that the seconds value can be 59.9, etc. (exlusive vs. inclusive)

This section summarizes all of the issues and pull requests that need to be resolved before we can finish. See Technical Agenda below for the focus of this meeting.

See PR #2522.

• MK: Arose from comments from Sheila Thomson about XSD1.0 and 1.1 differences for the value spaces in dateTime, and let systems that have schema processing to relax these dependencies.

The PR restricts the ability to relax these limits on XSD1.1 default in various version situations (see the diffs for detail) Also includes cases where coercion may be carried out in the string representation space. Some changes in F&O

ACTION QT4CG-156-01: MK: add reference to data model in F&O 9.2

• RD: i) There is a potential duplication in the XSLT spec with the data model spec. (Slightly different examples). Also some confusion about permitted character definitions between XSD 1.1 and 1.0 and extension of other permitted characters (that being '0'). MK: they should all refer to the data model, but there are some issues.

ACTION QT4CG-156-02: MK: think though implications on strings arising from duplication in specs.

Proposal: Accept this PR.

Accepted.

See PR #2519.

• MK: CG asked for a consistent record type of the plan data structure for the element-to-map() and corresponding plan generation functions. The proposal has a record type for the element plan and a separate record type for attributes.

An editorial change adding the predefined record types.

Proposal: Accept this PR.

Accepted.

See PR #2516.

• MK: We didn't discuss JNode identity thoroughly enough - this addresses that, mainly as extended notes on the jtree() function. Possibly most effect on the elimination of duplicate JNodes within a path.
• JLO: Is there some contradiction within these notes?
• MK: These equalities only occur in the same JNode tree, and the requirement is to support optimisation such as inlining results.
• RD: Unrolling a for loop over such a map might be such an example.
• MK: e.g. multiple serialisations across a program with the same options could involve optimisation of build a common single map.
• JLO: Not convinced - somewhat murky.
• MK: Don't want to repeat the problems node identity has raised in such optimisation situations. If you select the same parts by different paths then you will get the same JNodes. If you have an array with 17 identical maps, then they can't be considered the same, provided they have been generated in through the same JTree
• AP: Perhaps we should not rely on this - they are only guaranteed different if their contents differ.
• CG: We might make it easier if we omit all implementation details. Who are we trying to communicate with in the spec?
• WP: We have deep-equal() defined - what in addition are we trying to get.
• MK: The main use is the elimination of duplicates.
• JLO: Have a clearer image now - might be easier to move the thrid paragraph to the top of section 16.1.1 - the jtree() function.

ACTION QT4CG-156-03: MK to revise PR #2516 in light of the comments.

See PR #2515.

• MK: Didn't pick up all the suggestions from the issue. ElementTest and AttributeTest cahnged to type terms - purely terminology alterations. jnode(,) now unified to the element() and attribute()

Proposal: Accept the PR.

Accepted.

See PR #2504.

Proposal: Close without action.

Accepted.

See PR #2470.

Not ready for discussion.

See PR #2313.

• CG: now use (:DEFAULT-ON-EMPTY:) rather than (:empty:) in the signatures, before the default value.

ACTION QT4CG-156-04: CG: Related to #2313, make some minor changes to the explanatory note.

Proposal: Accept this PR.

Accepted.

See PR #2019.

Not ready for discussion.