IRC log of shapes on 2016-02-18

Timestamps are in UTC.

18:57:36 [RRSAgent]
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logging to
18:57:38 [trackbot]
RRSAgent, make logs rdf-data-shapes
18:57:38 [Zakim]
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18:57:40 [trackbot]
Zakim, this will be SHAPES
18:57:40 [Zakim]
I do not see a conference matching that name scheduled within the next hour, trackbot
18:57:41 [trackbot]
Meeting: RDF Data Shapes Working Group Teleconference
18:57:41 [trackbot]
Date: 18 February 2016
18:59:05 [Arnaud]
18:59:10 [Arnaud]
chair: Arnaud
18:59:31 [pfps]
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regrets: simonstey
18:59:35 [pfps]
18:59:47 [Arnaud]
19:00:52 [Arnaud]
present+ kcoyle
19:01:14 [aryman]
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19:01:50 [pfps]
19:01:55 [aryman]
present+ aryman
19:02:50 [hknublau]
19:03:36 [wippler]
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19:05:56 [Labra]
+present labra
19:06:31 [hsolbrig]
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19:06:55 [hsolbrig]
what is the webex password?
19:07:55 [jamsden]
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19:07:59 [pfps]
scribenick: pfps
19:08:10 [Arnaud]
present +jamsden
19:08:35 [pfps]
topic: Administrivia
19:08:46 [Arnaud]
PROPOSED: Approve minutes of the 11 February 2016 Telecon:
19:08:55 [aryman]
excellent scribing!
19:09:07 [pfps]
minutes looked OK
19:09:21 [Arnaud]
RESOLVED: Approve minutes of the 11 February 2016 Telecon:
19:09:35 [pfps]
arnaud: next meeting next week
19:09:44 [pfps]
topic: issue-68
19:10:20 [pfps]
arnaud: I added pointers to last discussion of issues
19:10:42 [pfps]
arnaud: there are some issues that have not had any discussion
19:10:50 [pfps]
arnaud: we should try to look at them
19:10:54 [pfps]
19:10:54 [trackbot]
ISSUE-68 -- pre-binding not defined in SHACL spec -- open
19:10:54 [trackbot]
19:11:20 [pfps]
arnaud: the last time this was discussed was in July 2015
19:11:47 [pfps]
arnaud: holger sent out an email with a proposal
19:12:16 [pfps]
holger: I had conversations on this with Andy Seabourne (sp?)
19:12:53 [pfps]
holger: There needs to be something done - there is no formal definition of pre-binding in SPARQL
19:13:04 [Arnaud]
19:14:08 [pfps]
holger: initial bindings are supported in implementations
19:14:33 [pfps]
holger: I don't see how to avoid something like pre-bindings
19:14:39 [ericP]
TallTed, does virtuoso support pre-binding?
19:14:55 [ericP]
19:15:10 [Arnaud]
present+ ericP
19:16:28 [pfps]
holger: andy suggested to use an algebra specification, using the operators there to get the effect of pre-bindings
19:16:37 [Arnaud]
ack ericP
19:17:10 [pfps]
eric: you could use bindings for this if you didn't rely on told b-nodes
19:17:49 [pfps]
eric: if you don't use b-nodes then you could get by
19:18:03 [pfps]
19:18:17 [Arnaud]
ack pfps
19:18:51 [pfps]
pfps: I don't think that this is the issue - this is not getting things in from the outside, it is for internal communication
19:19:15 [pfps]
holger: we agreed not to support SPARQL endpoints
19:19:16 [pfps]
19:19:43 [pfps]
arnaud: so this has not yet been addressed, there is a proposal
19:19:44 [Arnaud]
ack pfps
19:20:31 [pfps]
pfps: we do depend on this quite a bit as the internal need it
19:20:56 [pfps]
arnaud: it's not that the problem is not important, it's that it is not controversial
19:21:49 [pfps]
pfps: the current stuff is very hand-waving, and this needs to be nailed down sometime
19:24:08 [aryman]
19:24:50 [pfps]
pfps: it is possible that something in the SPARQL algebra works, I don't know whether ToMultiSet is the right thing
19:25:17 [pfps]
arnaud: if that is the right thing then that could be put into the spec
19:25:22 [pfps]
holger: OK
19:25:25 [Arnaud]
ack aryman
19:25:40 [pfps]
arthur: this is only an issue for the SPARQL binding
19:25:45 [pfps]
holger: right
19:26:34 [pfps]
arthur: this came up in SPARQL update, where they use SELECT clauses to get at blank node
19:26:55 [pfps]
arthur: it seems to me that the nodes that we need to identify are accessible in this manner
19:27:18 [pfps]
arthur: if you wanted to implement this on a remote endpoint then you could use this method
19:27:31 [pfps]
holger: this would work sometimes
19:27:58 [pfps]
arthur: holger will update the draft and we can see if the result is acceptable
19:28:12 [pfps]
topic: issue-92
19:28:15 [pfps]
19:28:15 [trackbot]
issue-92 -- Should repeated properties be interpreted as additive or conjunctive? -- open
19:28:15 [trackbot]
19:28:28 [pfps]
19:28:45 [pfps]
arnaud: there has been discussion on this topic
19:28:52 [aryman]
19:29:02 [Arnaud]
ack aryman
19:29:05 [pfps]
arnaud: we may not be able to get to the bottom of this today, but let's have an update
19:29:24 [pfps]
arthur: our discussion had to do with meta-model aspects
19:29:48 [pfps]
arthur: we have come to the conclusion to focus on the user-visible terms
19:30:10 [pfps]
arthur: I have just rewritten the text to eliminate non-visible stuff
19:30:44 [pfps]
19:31:51 [pfps]
eric: we have some amendmants to consider to match our needs
19:32:13 [pfps]
arthur: what's the status
19:32:24 [pfps]
eric: we are hoping to match this construct
19:32:29 [hknublau]
19:32:36 [pfps]
eric: we have nestings of expressions to consider
19:33:41 [pfps]
eric: we have arbitrary expressivity of groups,
19:33:50 [pfps]
eric: we want to make nesting of expressions simple
19:33:50 [aryman]
19:34:03 [pfps]
arnaud: that's encouraging
19:34:04 [Arnaud]
ack hknublau
19:34:33 [pfps]
holger: if we add this we also need to think about qualified cardinality expressions
19:35:05 [pfps]
arnaud: at some point we should think about removing things that are not needed
19:35:12 [Arnaud]
ack aryman
19:35:32 [pfps]
arthur: peter - on the proposal page you voted -1
19:35:53 [aryman]
19:36:34 [pfps]
pfps: at some point I will have to look at it again
19:37:40 [pfps]
arnaud: I don't know if looking at this next week is doable
19:38:21 [pfps]
topic: issue-47
19:38:23 [pfps]
19:38:23 [trackbot]
issue-47 -- Can SPARQL-based constraints access the shape graph, and how? -- open
19:38:23 [trackbot]
19:38:39 [pfps]
arnaud: we discussed this last week
19:39:13 [pfps]
arnaud: in some cases it is not possible to access the shapes graph
19:39:48 [Arnaud]
19:39:49 [pfps]
arnaud: there is a new proposal
19:40:14 [pfps]
19:40:39 [Arnaud]
ack pfps
19:41:19 [pfps]
pfps: my action in this area was to come up with a counter proposal but I have been to busy to do so
19:41:46 [Arnaud]
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19:42:29 [ericP]
[Request too long]
19:42:32 [ericP]
PROPOSAL: Close ISSUE-47, stating that: Not all execution environments can support $shapesGraph access, just like not all platforms have to support SPARQL extensions in general. However, for those environments that do, the spec should define $shapesGraph access and clarify that it is an optional feature. Implementations that do not support it may report a Failure. For the core built-ins, these implementations may use alternative approaches such as custom [CUT]
19:42:57 [Arnaud]
s/custo[CUT]/custom SPARQL code generators but that is left as an implementation detail. /
19:43:12 [hknublau]
19:43:17 [aryman]
19:43:18 [pfps]
19:43:20 [jamsden]
19:43:25 [ericP]
19:43:28 [hsolbrig]
19:43:29 [Labra]
19:43:29 [kcoyle]
19:44:55 [pfps]
pfps: why all the 0's people will use this feature
19:44:57 [Arnaud]
RESOLVED: Close ISSUE-47, stating that: Not all execution environments can support $shapesGraph access ...
19:45:18 [pfps]
topic: issue-52
19:45:33 [pfps]
19:45:33 [trackbot]
issue-52 -- Define an Abstract Syntax for SHACL -- open
19:45:33 [trackbot]
19:46:18 [pfps]
topic: issue-121
19:46:18 [ericP]
19:46:18 [trackbot]
issue-121 -- Should the SHACL owl:Ontology include the # character -- open
19:46:18 [trackbot]
19:46:20 [pfps]
19:46:20 [trackbot]
issue-121 -- Should the SHACL owl:Ontology include the # character -- open
19:46:20 [trackbot]
19:46:34 [aryman]
19:47:05 [pfps]
arnaud: there is a disagreement as to whether the # should be included
19:47:34 [pfps]
arnaud: there is little guidance to be found elsewhere
19:47:57 [Arnaud]
ack aryman
19:48:31 [pfps]
arthur: the best practice document doesn't bear on this issue, as we have already agreed to use # URIs
19:48:57 [pfps]
arthur: the document talks about whether to use # URIs or / URIs
19:49:52 [pfps]
arthur: W3C vocabularies use # URIs, mostly, which allows for a single document
19:50:45 [pfps]
arthur: the document says to use either a # or a slash at the end of the namespace names
19:50:56 [pfps]
arthur: # URIs end up being simpler
19:52:11 [hknublau]
19:52:16 [Arnaud]
STRAWPOLL: Should the SHACL owl:Ontology include the # character? Y/N
19:52:24 [pfps]
arthur: the question is whether to include the # in the name of the ontology
19:52:28 [Arnaud]
ack hknublau
19:53:03 [pfps]
holger: I agree that the OWL ontology should be the base URI and that this should not have #
19:53:30 [pfps]
holger: I asked Richard Cy... what the trend is, he says that the ontology does not not have #
19:53:52 [pfps]
arthur: let's not have two URIs
19:54:07 [pfps]
holger: W3C no longer uses that practice
19:54:18 [pfps]
arthur: I don't care
19:54:55 [Arnaud]
STRAWPOLL: Should the SHACL owl:Ontology include the # character? Y/N
19:54:58 [ericP]
q+ to say that it depends on constellation size
19:55:12 [Arnaud]
ack ericP
19:55:12 [Zakim]
ericP, you wanted to say that it depends on constellation size
19:55:55 [pfps]
eric: the decision on # or / depended on the size of the ontology, / for large
19:56:24 [ericP]
19:56:38 [pfps]
? - go with the flow
19:56:47 [hknublau]
19:56:53 [hsolbrig]
0 (do not care)
19:56:55 [kcoyle]
19:57:00 [pfps]
eric: it seems to me that it is easier of the prefix and the ontology are the same
19:57:19 [Labra]
Y (0,5)
19:57:27 [Labra]
N (0)
19:57:32 [aryman]
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19:57:37 [aryman]
dropped off
19:57:58 [pfps]
holger: if we include # then we also need to include the imports statement
19:58:04 [aryman]
please repeat the straw poll question
19:58:34 [Arnaud]
STRAWPOLL: Should the SHACL owl:Ontology include the # character? Y/N
19:58:45 [aryman]
19:59:00 [jamsden]
19:59:22 [pfps]
arnaud: more Y than N
19:59:33 [Arnaud]
PROPOSED: Close ISSUE-121, the SHACL owl:Ontology include the # character
19:59:41 [aryman]
19:59:49 [hknublau]
19:59:49 [Labra]
19:59:50 [pfps]
19:59:51 [ericP]
19:59:54 [hsolbrig]
19:59:55 [jamsden]
20:00:01 [kcoyle]
20:00:10 [Arnaud]
ack jamsden
20:00:29 [pfps]
jamsden: I ran into this when building the OLSC vocabulary
20:00:50 [aryman]
20:01:23 [pfps]
jamsden: i liked not having the # in the vocabulary name and having # at the beginning of the local names
20:01:39 [aryman]
20:01:52 [Arnaud]
ack aryman
20:02:23 [pfps]
arthur: for short URLs you can use relative URLs or CURIES
20:02:39 [ericP]
20:02:42 [pfps]
arthur: is # allowed at the beginning of a CURIE?
20:02:53 [Arnaud]
ack ericP
20:04:07 [Arnaud]
RESOLVED: Close ISSUE-121, the SHACL owl:Ontology include the # character
20:04:42 [pfps]
topic: issue-99
20:04:48 [pfps]
20:04:48 [trackbot]
issue-99 -- special treatment of rdfs:Resource and rdf:List in sh:valueClass (and possibly elsewhere) -- open
20:04:48 [trackbot]
20:05:11 [pfps]
arnaud: there was a proposal on the proposals page on this issue
20:05:42 [hknublau]
20:05:45 [pfps]
arnaud: I would like to get more eyes on this
20:05:47 [Arnaud]
ack hknublau
20:07:33 [pfps]
holger: this is about whether sh:valueClass should work for lists that are untyped and other special cases
20:08:38 [Arnaud]
pfps: completely disagree, why treating lists any differently? what's so special about them?
20:08:50 [pfps]
pfps: there is nothing special about lists
20:09:04 [pfps]
pfps: we have decided not to use inferencing
20:09:43 [pfps]
holger: but Turtle doesn't put type statements on lists
20:10:14 [aryman]
20:10:43 [Arnaud]
pfps: this is the result of not doing inferencing
20:11:16 [Arnaud]
pfps: this is just adding to the ugliness
20:11:20 [Arnaud]
ack aryman
20:11:43 [pfps]
arthur: what is the semantics of the collection construct
20:11:55 [pfps]
eric: just a bunch of triple - not the type triple
20:12:15 [pfps]
arthur: I think that this indicates a special treatment of lists
20:12:31 [pfps]
20:12:41 [Arnaud]
ack pfps
20:13:17 [pfps]
pfps: then the way to go is to have special syntax in SHACL for lsits
20:13:31 [aryman]
sounds promising
20:13:32 [pfps]
eric: agreed
20:13:37 [aryman]
what do you propose?
20:14:08 [pfps]
pfps: i guess it is on me
20:14:45 [pfps]
ACTION pfps: proposal for lists
20:14:45 [trackbot]
Created ACTION-35 - Proposal for lists [on Peter Patel-Schneider - due 2016-02-25].
20:15:19 [pfps]
topic: issue-105
20:15:22 [pfps]
20:15:22 [trackbot]
issue-105 -- SHACL SPARQL constraints depend on namespaces in a graph, which is not defined -- open
20:15:22 [trackbot]
20:15:43 [pfps]
arnaud: peter raised this issue
20:15:51 [Arnaud]
20:16:02 [pfps]
holger: I have a proposal on the proposals page
20:16:32 [pfps]
20:16:46 [pfps]
pfps: this is a major change to how SHACL works
20:16:47 [Arnaud]
ack pfps
20:17:20 [aryman]
20:17:23 [pfps]
pfps: SHACL used to take RDF graphs and now it takes something else
20:17:27 [Arnaud]
ack aryman
20:17:59 [pfps]
arthur: I am both worried about and sympathetic to this proposal
20:18:47 [hknublau]
20:18:57 [pfps]
arthur: within files there are prefixes, most processors remember these prefixes
20:19:14 [pfps]
arthur: holger is saying that we should take advantage of this
20:19:47 [pfps]
arthur: if the SHACL processor uses a prefix that is not in the RDF graph document
20:19:56 [pfps]
20:20:21 [pfps]
arthur: but if there is a prefix in the document then that can be used
20:20:49 [Arnaud]
ack hknublau
20:21:08 [pfps]
holger: I don't think that this is changing much
20:22:13 [pfps]
holger: this can be done in a pre-processing stage
20:22:48 [pfps]
holger: we could also have a triple linking
20:22:50 [Arnaud]
ack pfps
20:23:26 [hknublau]
20:24:08 [pfps]
pfps: this requires a 1-1 correspondence between SHACL inputs and documents, which is a bad idea
20:24:11 [Arnaud]
ack hknublau
20:24:29 [aryman]
aryman has joined #shapes
20:24:35 [pfps]
holger: if prefixes were part of RDF then that would be the best solution
20:25:14 [pfps]
holger: at a certain stage you have to have assumptions on how the data was processed
20:25:27 [aryman]
20:25:36 [pfps]
holger: if there are conflicting prefixes then the engine can throw an error
20:25:42 [Arnaud]
ack aryman
20:25:54 [pfps]
q+ to argue against pre-defined prefixes
20:26:17 [pfps]
arthur: in OSLC we have triples for the prefixes
20:26:57 [pfps]
arthur: when you print a graph you want to use CURIEs so we put triples in the file to give preferred prefixes
20:27:05 [aryman]
# Triples needed for code generation (to be deleted prior to final publication) <#process-prefix> a <> ; <> "sh" ; <> sh: .
20:27:49 [pfps]
arthur: the advantage here is that they only have to be done once and we are in an RDF world
20:28:18 [pfps]
arthur: any prefix in the SPARQL would override this
20:28:37 [Arnaud]
ack pfps
20:28:38 [Zakim]
pfps, you wanted to argue against pre-defined prefixes
20:30:11 [pfps]
pfps: I actually don't have any particular problem with special syntax that injects prefix declarations into the generated SPARQL
20:30:31 [pfps]
20:31:31 [Arnaud]
trackbot, close meeting
20:31:31 [trackbot]
Sorry, Arnaud, I don't understand 'trackbot, close meeting'. Please refer to <> for help.
20:31:40 [Arnaud]
trackbot, end meeting
20:31:40 [trackbot]
Zakim, list attendees
20:31:40 [Zakim]
As of this point the attendees have been pfps, Arnaud, kcoyle, aryman, hknublau, ericP
20:31:48 [trackbot]
RRSAgent, please draft minutes
20:31:48 [RRSAgent]
I have made the request to generate trackbot
20:31:49 [trackbot]
RRSAgent, bye
20:31:49 [RRSAgent]
I see 1 open action item saved in :
20:31:49 [RRSAgent]
ACTION: pfps to proposal for lists [1]
20:31:49 [RRSAgent]
recorded in