Re: on entailment

Peter, I have begun an informal list of issues being brought up so that 
we may go through them as a group. (It's easy to lose track in this 
complexity of email threads.) The page is:

https://www.w3.org/2014/data-shapes/wiki/Comments/September2016/

and I can see that it already goes beyond September, but I will try to 
keep it up to date as we go on, regardless of its title. I wouldn't say 
that it is complete today - I'm still digging through emails.

kc

On 10/1/16 8:08 AM, Peter F. Patel-Schneider wrote:
> This works for me, but does the working group agree with this change to SHACL?
>
> Peter F. Patel-Schneider
> Nuance Communications
>
> On 09/26/2016 04:32 PM, Holger Knublauch wrote:
>>
>>
>> On 27/09/2016 1:50, Peter F. Patel-Schneider wrote:
>>> On 09/26/2016 12:12 AM, Holger Knublauch wrote:
>>>>
>>>> On 26/09/2016 16:31, Peter F. Patel-Schneider wrote:
>>>>> "the property sh:entailment can be used to instruct a SHACL Full processor
>>>>> to ensure that a given entailment is activated on the data graph."
>>>>>
>>>>> Can SHACL Core processors "activate" entailment?
>>>> I have removed the term "Full" from this section.
>>>>
>>>> https://github.com/w3c/data-shapes/commit/ebeb18f61eea4bf3164ee183ca166a70a2f5cfce
>>>>
>>>>
>>>>
>>>> Indeed there could be implementations of less than SHACL Full that still
>>>> provide entailment support. However, the sh:entailment property lies outside
>>>> of SHACL, and this is clarified by the position of this paragraph in the Part
>>>> II of the spec.
>>> That works.
>>>
>>>>> "In addition to shape definitions, the shapes graph may contain additional
>>>>> information for the SHACL processor such as entailment directives."
>>>>>
>>>>> "If an entailment regime is provided in the data graph which is not
>>>>> supported by the SHACL Full processor, the validation must produce a
>>>>> failure."
>>>>>
>>>>> Where can the entailment directive/regime be?
>>>> I assume you mean what the subject of sh:entailment is? We have left this
>>>> undefined, i.e. it can be attached to any subject. A typical design pattern
>>>> would be to place it into an owl:Ontology node but since the shapes graph may
>>>> contain any number of them (owl:imported) we didn't want to open yet another
>>>> topic that may lead to controversial discussions
>>> The first quote above says that the entailment directive/regime is in the
>>> shapes graph.  The second quote says that if an unsupported entailment
>>> directive/regime is in the data graph then something is wrong.  This doesn't
>>> make sense.
>>
>> Yes, this was a bug in the spec. The sh:entailment triples must be in the
>> shapes graph. Clarified:
>>
>> https://github.com/w3c/data-shapes/commit/f7998dbaccf10e00333f05f87cb744c20f19d4a1
>>
>>
>> Thanks
>> Holger
>>
>>
>
>

-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
m: 1-510-435-8234
skype: kcoylenet/+1-510-984-3600

Received on Saturday, 1 October 2016 16:32:52 UTC