Re: shapes-ISSUE-112 (misuse of RDFS properties): SHACL uses RDFS properties in ways that violate their intended RDFS meaning [SHACL Spec]

Shapes are groupings of constraints.

For example, PersonShape may include (group) a constraint about personıs
gender, another constraint about their age and a third constraint about a
number of parents a person may have.

There are (at least) three ways to say that a particular constraint is
part of a shape. sh:property is one of them.

ex:someProperty is part of the constraint itself. In the example, above,
it may be ex:gender. And ex:gender may have a label of its own - ³gender"

rdfs:label and rdfs:comment are being used to say this constraint should
use a different label for the predicate. For example, ³gender (M/F)².

Irene Polikoff




On 11/6/15, 2:39 PM, "Karen Coyle" <kcoyle@kcoyle.net> wrote:

>Does "for the property in the scope where it appears" refer to
>sh:property or ex:someProperty in the example? It cannot be
>ex:someProperty because that isn't a rdf:Resource in the graph -- it's
>never a subject of a triple. All of the predicates in the sh:property
>[...] graph have sh:property as their subject.
>
>Now I'm fully confused about the whole sh:property graph and what the
>predicates in the graph mean. I should probably take a walk and think
>about it later.
>
>kc
>
>On 11/6/15 9:40 AM, Peter F. Patel-Schneider wrote:
>> rdfs:label and rdfs:comment are supposed to be about the resource
>>itself,
>> which for SHACL is a constraint or shape.  However, the wording in
>>SHACL says
>> to make them about the property, which is different from the constraint
>>or shape.
>>
>> For example, the SHACL example is
>>
>> ex:InlinePropertyConstraintExampleShape
>> 	a sh:Shape ;
>> 	sh:property [
>> 		sh:predicate ex:someProperty ;
>> 		sh:minCount 1 ;
>> 		sh:valueClass ex:SomeClass ;
>> 		rdfs:label "some property" ;
>> 		rdfs:comment "This is used for some purpose" ;
>> 	] .
>>
>> where as it really should be
>>
>> ex:InlinePropertyConstraintExampleShape
>> 	a sh:Shape ;
>> 	sh:property [
>> 		sh:predicate ex:someProperty ;
>> 		sh:minCount 1 ;
>> 		sh:valueClass ex:SomeClass ;
>> 		rdfs:label "ex:someProperty constraint in
>> ex:InlinePropertyConstraintExampleShape" ;
>> 		rdfs:comment "This constrains values of ex:someProperty to belong to
>> ex:someClass" ;
>> 	] .
>>
>> peter
>>
>>
>> On 11/06/2015 07:40 AM, Karen Coyle wrote:
>>> Peter, this is a bit overly subtle for me. Can you say what exactly
>>>you see as
>>> violating RDFS? I'll tell you what I see and you can tell me how I'm
>>>wrong ;-)
>>> - when a property is itself a resource (X rdfs:label Y) then this has
>>>the RDFS
>>> meaning. What I see is that the resource that is named with rdfs:label
>>>in the
>>> case of SHACL is the blank node.
>>>
>>> Now, what's the real problem? I assume it's not just wording.
>>>
>>> Thanks,
>>> kc
>>>
>>> On 11/5/15 3:57 PM, Holger Knublauch wrote:
>>>> I had long thought about using new properties such as sh:label and
>>>> sh:definition instead. I decided to prefer rdfs:label and
>>>>rdfs:comment,
>>>> because these properties are most likely already used as annotations
>>>>on
>>>> the shapes, classes and other resources in SHACL files. People will
>>>>get
>>>> confused which property to use in which context, adding just another
>>>> unnecessary complication in the learning curve.
>>>>
>>>> Since a property constraint resource describes the use of a property
>>>>in
>>>> the context of a shape scope, I see no reason why using rdfs:label
>>>>would
>>>> violate the official spec.
>>>>
>>>> PROPOSAL: Close ISSUE-112 - no change required.
>>>>
>>>> Holger
>>>>
>>>>
>>>> On 11/6/2015 7:55, RDF Data Shapes Working Group Issue Tracker wrote:
>>>>> shapes-ISSUE-112 (misuse of RDFS properties): SHACL uses RDFS
>>>>> properties in ways that violate their intended RDFS meaning [SHACL
>>>>>Spec]
>>>>>
>>>>> http://www.w3.org/2014/data-shapes/track/issues/112
>>>>>
>>>>> Raised by: Peter Patel-Schneider
>>>>> On product: SHACL Spec
>>>>>
>>>>> >From http://w3c.github.io/data-shapes/shacl/:
>>>>>
>>>>> Property constraints may have an rdfs:label to provide a
>>>>> human-readable label for the property in the scope where it appears.
>>>>>
>>>>> >From http://www.w3.org/TR/rdf-schema/
>>>>>
>>>>> rdfs:label is an instance of rdf:Property that may be used to provide
>>>>> a human-readable version of a resource's name.  A triple of the form:
>>>>> R rdfs:label L . states that L is a human readable label for R.
>>>>>
>>>>> The SHACL use does not abide by the RDFS meaning.  SHACL should not
>>>>> use RDFS properties in ways that violate their RDFS meaning.
>>>>>
>>>>> Similarly for rdfs:comment.
>>>>>
>>>>>
>>>>> PROPOSAL:  Remove the non-conforming wording for and uses of
>>>>> rdfs:label and rdfs:commment.
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>
>>
>>
>
>-- 
>Karen Coyle
>kcoyle@kcoyle.net http://kcoyle.net
>m: 1-510-435-8234
>skype: kcoylenet/+1-510-984-3600
>

Received on Friday, 6 November 2015 20:37:10 UTC