W3C

RDF Data Shapes Working Group Teleconference

14 May 2015

Agenda

See also: IRC log

Attendees

Present
pfps, Arnaud, hknublau, [IPcaller], kcoyle, ericP, TallTed, aryman, Dimitris, michel_(partially)
Regrets
SimonSteyskal, hsolbrig, cygri
Chair
Arnaud
Scribe
hknublau

Contents


<ericP> having a hard time dialing it

<Arnaud> scribenick: hknublau

Admin

Arnaud: Not clear if ISSUE-46 is closed (It is not).

<Arnaud> PROPOSED: Approve minutes of the 7 May Telecon: http://www.w3.org/2015/05/07-shapes-minutes.html

<pfps> minutes looked fine to me

RESOLUTION: Approve minutes of the 7 May Telecon: http://www.w3.org/2015/05/07-shapes-minutes.html

Tracking of Actions and Issues

<michel> regrets, i have a conflict

<scribe> no progress on open actions

Agenda for F2F next week

Arnaud: Current agenda just there to outline meeting times

… we may start discussing test cases even if no draft is there yet

… I hope next meeting will be real face to face again

… Report from social WG, which also has entrenched groups with three proposals

… at the last F2F of that report, we had in-depth dives for each proposal, based on (general enough) user stories

… goal was to increase understanding, then self-criticism session.

… some magic happened: collaboration improved, possible convergence points identified

aryman: what we need is a process to pick a document

… we could create sample data to be validated

<kcoyle> Arnaud: +1, maybe a miracle will happen, but we won't know without trying

<pfps> shapes as classes is a detail, not a fundamental issue

+q

hknublau: classes vs shapes is independent of draft selection, needs to be answered in any case

<kcoyle> +q

aryman: lots of issues are cross-cutting, we should avoid triplicating efforts to improve efficiency of discussion

kcoyle: Pushing hard for specific examples, happy to provide examples

<ericP> +1 to arnaud's proposal

<pfps> I'm willing to do the work required

arnaud: Presenters could prepare user stories based on specific examples

… an hour per proposal, “demo”

… “what would it take for the other proposals to be acceptable” -> compromises

+q

<pfps> I view the ShEx proposal as *very* different from the other two.

hknublau: Drafts mainly differ in ways that things are formalized, not so much on surface syntax

arnaud: Traffic has slowed down a bit, is everyone just frustrated?

<pfps> As far as I am concerned, the issues that have been discussed matter very little to me, so I have not been posting much.

pfps: ShEx proposal is completely different from the other two ones, despite SPARQL fallback

<pfps> s/issues/discussion/ in my typed comment

arnaud: if this meeting doesn’t lead to starting point, we are in real trouble with schedule.

Requirements

<Arnaud> http://www.w3.org/2014/data-shapes/track/issues/46

<Arnaud> https://lists.w3.org/Archives/Public/public-data-shapes-wg/2015May/0017.html

Arnaud: is issue resolved now that the requirement is written down?

<pfps> I think that the two requirements address the need for validating rdf:Lists, so ISSUE-46 can be closed. This is *separate* from actually approving the requirements.

<Arnaud> PROPOSED: Close ISSUE-46 by adding requirements 2.6.12 and 2.6.13 as proposed by Richard in: https://lists.w3.org/Archives/Public/public-data-shapes-wg/2015May/0017.html

+1

<TallTed> +1

<pfps> There are lots of aspects of RDF documents that the WG is not addressing.

<pfps> +1

<aryman> +1

<Dimitris> +1

<pfps> +1 to adding the requirements to the requirements page (i'm also in favour of approving the requirements, by the way)

<Labra> +1

RESOLUTION: Close ISSUE-46 by adding requirements 2.6.12 and 2.6.13 as proposed by Richard in: https://lists.w3.org/Archives/Public/public-data-shapes-wg/2015May/0017.html

<kcoyle> +1

SHACL Spec

<Arnaud> PROPOSED: open ISSUE-49

http://www.w3.org/2014/data-shapes/track/issues/49

pfps: unclear about distinction, ShEx doesn’t have scoped vs unscoped shapes, neither is it essential to the others.

… not sure if this distinction matters

Dimitris: yes it is a technical question

TallTed: This seems to be about nested shapes, if you have more than zero of something, then they must be within constraints

Dimitris: Mostly about complexity

<pfps> leave as is

Arnaud: Shall we close and later reopen, or just wait?

aryman: In Holger’s draft this is more like a filter condition

<pfps> In my proposals, all shapes are unscoped. They only get a scope in use.

<pfps> s/proposals/proposal/ :-)

… Hard to discuss without having a draft first, we should delay this topic

… can we postpone it in issue tracker?

<Arnaud> PROPOSED: Postpone ISSUE-49

<aryman> +1

+1

<kcoyle> +1

<Dimitris> +1

<Labra> +1

<TallTed> +1

RESOLUTION: Postpone ISSUE-49

<Arnaud> https://www.w3.org/2014/data-shapes/wiki/User_Stories#S43:_Using_Property_Paths_for_Property_Value_Comparison

+q

<kcoyle> +q

hknublau: I believe notEqual doesn’t belong into the core - too specific. Can already be handled by macros + SPARQL, already approved

aryman: Does not look like a compelling example yet

kcoyle: Can we agree on term “Core”

Arnaud: Maybe we can extend the core now to make everyone happy, reduce resistance against SPARQL extensions.

<pfps> It's too soon to dispose of S43

pfps: S44 requires revision, mangled

<pfps> the body of S44 is completely unrelated to issue-42

Arnaud: let’s move on

<Arnaud> issue-48?

<trackbot> issue-48 -- How do we limit the scope for a shape? -- open

<trackbot> http://www.w3.org/2014/data-shapes/track/issues/48

pfps: Title is misleading

… Michel (probably) wants the scope to be more than for example class membership

Arnaud: Michel should take another pass at the issue

<pfps> The title of ISSUE-48 talks about how to limit the scope of shapes, which all proposals have. The body talks about scopes of shapes that go beyond just individuals and class extensions.

<michel> coming

michel: whether or not we can select data for a shape, not for all data but for selected data only

<pfps> I'm still confused as to whether Michel wants scopes on shapes or expressive scopes on shapes.

aryman: Are you asking for a requirement or propose a design?

<pfps> Every proposal has scopes on shapes.

<pfps> Some proposals only have limited kinds of scopes allowable.

+q

<pfps> As Holger says, there are already requirements for instance and class scopes.

<pfps> I agree with Holger that expressive scopes are useful.

hknublau: scope as precondition is not yet captured by requirements

<Dimitris> I also agree to include general scopes

<pfps> An expressive scope would work just like a class-based scope - I don't see any difference.

<pfps> Of course, there may be effects of allowing expressive scopes.

aryman: if precondition fails then the constraint may be true

+q

<aryman> its like an if-then

<pfps> For example you could have a scope be all nodes that are objects of a particular property - if the type is rdf:type then this is (close to) class scopes

<pfps> I'm not sure why "core" is again raising its head

hknublau: maybe scopes should go into another sub-dialect than “core”

aryman: dynamic forms are a frequent requirement, as long as scopes are nice and declarative, they should be supported by core

<michel> just lost power

<michel> lol

pfps: I am in favor of adding this requirement for expressive scopes, separate from core-or-not

<pfps> PROPOSED: Close ISSUE-48 by adding a requirement that the effect of expressive scopes be in SHACL

+1

<aryman> +1

<Dimitris> +1

<michel> +1

<kcoyle> +1

<TallTed> +1

<Labra> +1

<pfps> I'm willing to write the requirements

RESOLUTION: Close ISSUE-48 by adding a requirement that the effect of expressive scopes be in SHACL

<pfps> ACTION: pfps to write requirement coming from ISSUE-48 [recorded in http://www.w3.org/2015/05/14-shapes-minutes.html#action01]

<trackbot> Created ACTION-24 - Write requirement coming from issue-48 [on Peter Patel-Schneider - due 2015-05-21].

http://www.w3.org/2014/data-shapes/track/issues/23

<Arnaud> ISSUE-23?

<trackbot> ISSUE-23 -- Shapes, classes and punning -- open

<trackbot> http://www.w3.org/2014/data-shapes/track/issues/23

+q

TallTed: some of the discussion in last meeting was about the flexibility to allow mixing classes and shapes

… to avoid having to rewrite their ontology with shapes, reusing the same URI should be allowed

… does not mean that every shape is a class or every class is a shape. 

… allow people to do things more efficiently

Arnaud: We cannot really prevent users from mixing classes and shapes anyway

TallTed: Tools that don’t understand shapes can ignore the shape aspect

<pfps> But if I am a shape-aware system and I see a shape that is also a class am I obligated to run the shape on all instances of the class?

… owl:sameAs has been abused, but if you can selectively ignore certain sameAs triples, it’s fine.

<Dimitris> +q

ericP: still have to copy OWL restrictions into shape, so this doesn’t help you much

<pfps> +1 to eric

aryman: from Linked Data point of view, class is global, but may have different interpretations per graph

… if class definition is local then I have no discomfort

Dimitris: Allowing the same URI is OK, but would prefer to keep metaclasses distinct.

<ericP> no one tells you what to do in the privacy of your own triple stoer

<ericP> store

Arnaud: Would prefer a solution that accommodates both design patterns.

<Arnaud> trackbot, end meeting

Summary of Action Items

[NEW] ACTION: pfps to write requirement coming from ISSUE-48 [recorded in http://www.w3.org/2015/05/14-shapes-minutes.html#action01]
 

Summary of Resolutions

  1. Approve minutes of the 7 May Telecon: http://www.w3.org/2015/05/07-shapes-minutes.html
  2. Close ISSUE-46 by adding requirements 2.6.12 and 2.6.13 as proposed by Richard in: https://lists.w3.org/Archives/Public/public-data-shapes-wg/2015May/0017.html
  3. Postpone ISSUE-49
  4. Close ISSUE-48 by adding a requirement that the effect of expressive scopes be in SHACL
[End of minutes]

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$Date: 2015/05/28 20:33:45 $