ISO/IEC JTC1 SC22 WG17 Minutes of 39th meeting via Zoom
Date of meeting: 2026-06-01
Time of meeting: 16:00 - 17:16 UTC

Ad 1. Greeting and introduction of participants, administrativa

Klaus Däßler (Germany)
Stefan Kral (Austria)
Manuel Hermenegildo (Spain)
Jose Morales (Spain)
Johan Ponin (France)
Markus Triska (Austria)
Ulrich Neumerkel (convener)

Invited non-member experts:
Andrew Davison (Australia) andrew.davison@gmail.com
Emily Easteal (United Kingdom) emily.easteal@gmail.com
Fred Mesnard (France) frederic.mesnard@univ-reunion.fr
Alex Petros (US) contact@alexpetros.com
Mark Thom (Canada) markjordanthom@gmail.com

Ad 1.1, minutes of 2025 meeting N306 were approved.

Ad 1.2, Law as Code

Markus Triska and Alex Petros presented, referring to

https://bmds.bund.de/themen/staatsmodernisierung/law-as-code
https://www.sprind.org/en/actions/strategic-projects/law-as-code
https://www.sovereign.tech/programs/standards
https://vatmiraal.be/

Prolog implementation of the IRS Fact Graph

Ad 1.3 Unicode characters (DTS 13211-4)
Markus Triska reported; ongoing N307.

Ad 1.4 Retaining clause numbering in existing standards.
No progress beyond SC22.

SC22 plenary 2025-09-08 action item in N6042:

2) JTC 1/SC 22 Chair to request an exception for the next revision of
ISO/IEC 13211-1 for subclause renumbering and hanging paragraphs. Most
notably, the syntax definition of term (6.3 Terms IS 13211-1:1995) is
spread over 16 production rules for the same non-terminal spanning
hanging paragraphs and over 11 subclauses. A renumbering would
unavoidably lead to confusion thereby contravening the purpose of
standards as a reliable reference.

Ad 2.1 Recent progress in Prolog systems

Emily Easteal presented new system Flowlog.

Trealla now conforms fully to quads for phrase, digit separators,
and double bar.

On reviewing new conformity tests #337 up to #364.
No issues requiring an immediate reaction were identified.

number_chars/2 testcases were reviewed.

Ad 2.2 Further corrigenda

stc#62 up to 69 were reviewed.
No issues requiring an immediate reaction were identified.

Ad 2.3 Syntax extension double bar

https://www.complang.tuwien.ac.at/ulrich/iso-prolog/double_bar

Currently supported by Ciao, Trealla, Modified Scryer.  Resolution for
next TS.

Ad 2.4 Syntax extension digit separators

https://www.complang.tuwien.ac.at/ulrich/iso-prolog/digit_separators

Currently SWI, Trealla, Scryer partially, Modified Scryer. No
resolution for next TS.

Ad 2.5 Prolog prologue

call_nth/3, countall/2 discussed, need for permutation/2.

2.6 crypto_data_hash/3

https://www.metalevel.at/iso-prolog/crypto_data_hash
https://github.com/mthom/scryer-prolog/issues/1137#issuecomment-4430540510

Flowlog first ISO Prolog based implementation

Resolution A1:

WG17 resolves to chose TS Syntax extension double bar as the work item
after 13211-4.

Unanimous.


3. Other activities

3.0 2026 PIP ICLP July Lisbon

3.1 Scryer meetups

Duesseldorf 2025-11-13..14.
Forthcoming, TU Wien, Vienna Saturday 2026-10-24, Sunday 2026-10-25.
https://www.digitalaustria.gv.at/wissenswertes/events/scryerprologmeetup2026.html

Meeting adjourned 17:16 UTC.

The next annual meeting will be Monday, June 7th 2027.