Re: Follow-up on Michel's comment

On 3/20/2015 10:37, Michel Dumontier wrote:
> Hi Holger,
>   I want a language that sits on its own, with a clearly defined 
> syntax and semantics, and for which there can be a number of 
> implementations. Since SPARQL is an obvious choice, it makes sense to 
> have a document that specifies how SHACL expressions can be evaluated 
> using SPARQL.

Yes, this language is currently called SHACL Core Profile (or SHACL 
Lite) and described in sections 2 - 6. It also has a SPARQL 
specification in the later chapters of the document. The Core Profile 
could have other formal definitions in separate deliverables, yet the 
consensus was that SPARQL should be used where possible.

>
>  What I worry about is that some users will simply resort to the 
> templating mechanism instead of articulating the constraint using the 
> language, thereby neatly causing a crisis in interoperability. You 
> seem to dismiss this possibility, but I'd rather be proactive on the 
> point, and emphasize that the templating mechanism should be used 
> where SHACL standardization fails to support a use case. With your 
> vast experience, it would also be useful to include use cases so that 
> users can see how the templating can get them further.

Yes of course, it should already be clear that people SHOULD use the 
built-in templates whenever they can. If there are means to make this 
recommendation even stronger, I'd be happy to hear about that.

>
> I also worry that those who wish to implement SHACL will be forced to 
> parse and interpret the arbitrary SPARQL expressions in templates. 
> Therefore, it's important to recognize that the templates, just as 
> much as functions, is a "if you need to do this, here's the vocabulary 
> for it", but there's no mandate by us that you have to interpret this. 
> Some will, and others won't.

Yes that describes the current plan.


> Thus, I'm ok with having clearly delineated profiles to handle these 
> cases.
> hope that clears up what i meant,

The reason why I picked on this question (and apologies for drilling 
down on your statement), is that the WG struggles with the decision on 
how many normative deliverables should be produced. Can I interpret your 
statements above that you would not object to a single document as long 
as it has clearly delineated profiles?

Holger

Received on Friday, 20 March 2015 01:39:41 UTC