Re: type and instance and subclass in SHACL documents

We are now back to

"""2.2 rdfs:Class
This is the class of resources that are RDF classes. rdfs:Class is an instance
of rdfs:Class."""

rdfs:Class is an RDFS instance of rdfs:Class.
rdfs:Class is not a SHACL instance of rdfs:Class.

peter




On 03/11/2016 02:35 PM, Irene Polikoff wrote:
> I still don’t know what you mean.
> 
> You believe that SHACL notion of instance is different from RDFS notion of
> instance and, thus, the sentence "This can be read to mean "RDFS instance"
> or "SHACL instance” has some meaning to you. I don’t know why and how they
> are different and I am not sure anyone else in the working group does, so
> this sentence has no meaning to me.
> 
> 
> I might understand better if you explained what input is provided to SHACL
> engine in the first case (no validation error) and in the second case
> (validation error).
> 
> Irene 
> 
> 
> 
> On 3/11/16, 5:22 PM, "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
> wrote:
> 
>> The definition of SHACL depends on "instannce".  This can be read to mean
>> "RDFS instance" or "SHACL instance".  Under the former meaning the data
>> graph
>> does not validate against the shape.   Under the latter meaning the data
>> graph
>> does validate against the shape.
>>
>> peter
>>
>>
>> On 03/11/2016 02:15 PM, Irene Polikoff wrote:
>>> I don¹t understand what you mean by
>>>
>>> "validates against this shape under SHACL instance but not under RDFS
>>> instance.²
>>>
>>> I am not able to parse the sentence.
>>>
>>> What are you doing? Taking a shape described and the graph described and
>>> running it against SHACL engine? What execution validates and what
>>> execution doesn¹t validate?
>>>
>>>
>>>
>>> Irene 
>>>
>>>
>>>
>>> On 3/11/16, 5:03 PM, "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
>>> wrote:
>>>
>>>> On 03/11/2016 01:01 PM, Karen Coyle wrote:
>>>>>
>>>>>
>>>>> On 3/11/16 11:43 AM, Peter F. Patel-Schneider wrote:
>>>>>> Consider the following shape (using obvious prefix declarations)
>>>>>>
>>>>>> sh:propertyShape a sh:Shape ;
>>>>>>   sh:scopeClass rdf:Property ;
>>>>>>   sh:property [ sh:predicate rdfs:label ;
>>>>>>                 sh:minCount 1 ] .
>>>>>>
>>>>>> The data graph (using obvious prefix declarations)
>>>>>>
>>>>>> rdfs:range ex:label "range" .
>>>>>>
>>>>>> validates against this shape under SHACL instance but not under RDFS
>>>>>> instance.
>>>>>
>>>>> Isn't this a problem with every vocabulary and not just RDFS? If the
>>>>> rules of
>>>>> the vocabulary (such as domain and range) are not encoded as such in
>>>>> SHACL
>>>>> then the SHACL result can be "in violation" of the vocabulary
>>>>> definition.
>>>>>
>>>>> Now, if that is the case then I understand that violating the
>>>>> foundation
>>>>> vocabulary of RDF/RDFS may be more grave than violating a
>>>>> user-developed
>>>>> vocabulary, and in some cases doing the latter may indeed be the
>>>>> intention of
>>>>> the SHACL definition. So do we want to build into SHACL that it must
>>>>> follow
>>>>> RDF/RDFS property and class definitions? And how feasible is that?
>>>>>
>>>>> kc
>>>>>
>>>>
>>>> This is only a real problem because SHACL uses "instance" in its
>>>> specification, this term is also used centrally in RDFS, and SHACL uses
>>>> RDFS
>>>> vocabulary.
>>>>
>>>> The question then is how to read "instance" in SHACL documentation,
>>>> i.e.,
>>>> how
>>>> to prevent readers of the SHACL documentation from seeing "RDFS
>>>> instance"
>>>> where "SHACL instance" is meant.
>>>>
>>>>
>>>> peter
>>>>
>>>
>>>
> 
>

Received on Saturday, 12 March 2016 00:36:00 UTC