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Re: Simplification of scopes section (see also ISSUE-148)

From: Karen Coyle <kcoyle@kcoyle.net>
Date: Thu, 19 May 2016 19:05:32 -0700
To: public-data-shapes-wg@w3.org
Message-ID: <573E70EC.90901@kcoyle.net>
Great, thanks Holger. That's what I wanted to confirm. None of the 
examples showed this so I wasn't sure.

kc

On 5/19/16 3:43 PM, Holger Knublauch wrote:
> Karen, I see nothing invalid in your example. Are you referring to the
> value of sh:valueShape being a bnode? Yes, this is perfectly fine, just
> like such bnodes can show up in sh:or and sh:not.
>
> Holger
>
>
> On 20/05/2016 3:56, Karen Coyle wrote:
>> Thanks, Simon. Looking at the code in your message in January, I am
>> wondering if this, below, a variant using a bnode, is valid SHACL -
>>
>> ex:IssueShape a sh:Shape;
>>   sh:scopeClass ex:Issue ;
>>   sh:property [
>>       sh:predicate ex:submitter ;
>>       sh:valueShape [
>>         a sh:Shape
>>         sh:scopeClass ex:Person ;
>>             sh:property [
>>                   sh:predicate ex:username ;
>>                   sh:minCount 1 ;
>>                   sh:maxCount 1 ;
>>           ]
>>       ]
>>
>> The examples all show nodes with IRIs. If a bnode is also valid, then
>> we should add a short example showing that. If not, then the document
>> should explain that.
>>
>> kc
>>
>> On 5/19/16 7:37 AM, Dimitris Kontokostas wrote:
>>> IIRC, This is the proposal we voted for
>>> https://lists.w3.org/Archives/Public/public-data-shapes-wg/2015Dec/0044.html
>>>
>>>
>>> and there were some followup questions e.g. the following that was
>>> tagged by mistake under a different issue
>>> https://lists.w3.org/Archives/Public/public-data-shapes-wg/2016Jan/0015.html
>>>
>>> here it is clarified that scoping and filters are ignored when the
>>> shapes are referenced from another shape
>>>
>>>
>>>
>>> On Thu, May 19, 2016 at 4:59 PM, Karen Coyle <kcoyle@kcoyle.net
>>> <mailto:kcoyle@kcoyle.net>> wrote:
>>>
>>>     Thanks. Can you describe or point me to the resolution? - kc
>>>
>>>     On 5/18/16 10:59 PM, Dimitris Kontokostas wrote:
>>>
>>>         Karen,
>>>
>>>         This is an issue I raised sometime ago and we have a resolution
>>>         with the
>>>         current design
>>>         https://www.w3.org/2014/data-shapes/track/issues/49
>>>
>>>
>>>         On Thu, May 19, 2016 at 3:26 AM, Holger Knublauch
>>>         <holger@topquadrant.com <mailto:holger@topquadrant.com>
>>>         <mailto:holger@topquadrant.com <mailto:holger@topquadrant.com>>>
>>>         wrote:
>>>
>>>              Not all shapes need to have a scope IMHO. It's the same
>>>         situation as
>>>              in ontology development. Not every class that is published
>>>         in an
>>>              ontology is used by everyone, and thus does not need to
>>> have
>>>              instances. Sometimes shapes will be defined in one file so
>>>         that they
>>>              can be extended with a scope in another file, for one
>>> specific
>>>              application.
>>>
>>>              I don't see a problem with our current design, and
>>>         sh:scopeProperty
>>>              being sometimes a bit redundant. As I said elsewhere,
>>> there are
>>>              cases where sh:scopeProperty and sh:predicate are in fact
>>>         different.
>>>              I would not favor introducing a new concept for nested
>>> shapes.
>>>
>>>              Holger
>>>
>>>
>>>
>>>
>>>              On 19/05/2016 2:22, Karen Coyle wrote:
>>>
>>>
>>>
>>>                  On 5/15/16 10:37 AM, Peter F. Patel-Schneider wrote:
>>>
>>>                      If all shapes are to have scopes then there are
>>>         ways around
>>>                      this problem.  One
>>>
>>>                              would be that shapes are not embedded in
>>> other
>>>                              shapes.  Instead there would be
>>>                              a new kind of SHACL thing that is used
>>> when the
>>>                              current effect of embedding
>>>                              shapes in shapes is desired.
>>>
>>>
>>>                  +1. I can't think of a good name for these, but it
>>>         seems to me
>>>                  that we have:
>>>
>>>                  SHACL "file" (data set, whatever) - a set of shapes and
>>>         constraints
>>>                  shape - defines a scope, optional filters, and related
>>>         constraints
>>>                  constraint - the node that defines a set constraints
>>>         that will
>>>                  be applied to the focus node
>>>                  [X] - a set of constraints
>>>
>>>                  [X] can be a blank node, as it is in many shapes, or it
>>>         may have
>>>                  an IRI, which is what was formerly illustrated in
>>>         Example 1.
>>>                  (This assumes that the only difference between them is
>>>         IRI-v-bNode.)
>>>
>>>                  The "embedded" vs. "referenced" doesn't make sense in
>>>         an RDF
>>>                  context, to my mind. It has instead to do with
>>> whether the
>>>                  constraints are local-only (bnode) or shareable (IRI).
>>>
>>>                  kc
>>>                  p.s. This doesn't take into account Holger's latest
>>>         proposal to
>>>                  place shapes sub constraints, but I don't think that
>>>         makes a
>>>                  difference here
>>>
>>>
>>>
>>>
>>>
>>>
>>>         --
>>>         Dimitris Kontokostas
>>>         Department of Computer Science, University of Leipzig & DBpedia
>>>         Association
>>>         Projects: http://dbpedia.org, http://rdfunit.aksw.org,
>>>         http://aligned-project.eu
>>>         Homepage: http://aksw.org/DimitrisKontokostas
>>>         Research Group: AKSW/KILT http://aksw.org/Groups/KILT
>>>
>>>
>>>     --
>>>     Karen Coyle
>>>     kcoyle@kcoyle.net <mailto:kcoyle@kcoyle.net> http://kcoyle.net
>>>     m: 1-510-435-8234
>>>     skype: kcoylenet/+1-510-984-3600 <tel:%2B1-510-984-3600>
>>>
>>>
>>>
>>>
>>> --
>>> Dimitris Kontokostas
>>> Department of Computer Science, University of Leipzig & DBpedia
>>> Association
>>> Projects: http://dbpedia.org, http://rdfunit.aksw.org,
>>> http://aligned-project.eu
>>> Homepage: http://aksw.org/DimitrisKontokostas
>>> Research Group: AKSW/KILT http://aksw.org/Groups/KILT
>>>
>>
>
>
>

-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
m: 1-510-435-8234
skype: kcoylenet/+1-510-984-3600
Received on Friday, 20 May 2016 02:05:58 UTC

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