Re: on divergence between textual and SPARQL definitions

My message states that this is pre-bound, so no.  If this pre-binding isn't
stated in the document then that would be another problem that needs to be fixed.

peter

On 12/09/2016 02:39 AM, Dimitris Kontokostas wrote:
> Peter, is this an indirect issue of the validators definition where we do not
> explicitly state that $this is prebound to the focus node?
> http://w3c.github.io/data-shapes/shacl/#constraint-components-validators
> 
> 
> On Fri, Dec 9, 2016 at 12:19 PM, Andy Seaborne <andy@apache.org
> <mailto:andy@apache.org>> wrote:
> 
>     Peter,
> 
>     On 09/12/16 02:46, Peter F. Patel-Schneider wrote:
>     ...
> 
>         The SPARQL definition here uses the following SPARQL query
> 
>         SELECT DISTINCT $this ?value
>         WHERE {
>           $this ex:p ?value .
>           FILTER NOT EXISTS
>             { $value rdf:type/rdfs:subClassOf* $class . }
>           }
> 
>         with this pre-bound to ex:n and class pre-bound to ex:c.
> 
>         According to the SHACL document
>         evaluating this SPARQL query will produce a non-empty solution sequence,
>         namely
>           { { (this, ex:m), (value,ex:l) } }
>         because
>           $this ex:p ?value .
>         will produce the set of solutions
>           { { (this, ex:n), (value,ex:m) } ,
>             { (this, ex:m), (value,ex:l) } }
> 
> 
>     I don't follow this part.
> 
>     On just the " $this ex:p ?value ." pattern, why, when ?this=ex:n, is the
>     second solution present?
> 
>     I think there is only one match. { { (this, ex:n), (value,ex:m) } }
>     and then the overall result is zero rows.
> 
> 
>     For both proposal-A and proposal-B used for pre-binding, that seems to be
>     the case.  $this is restricted before the FILTER is applied.
> 
>     (NB I acknowledge that Proposal-A is not proposed for pre-binding and
>     wasn't suggested as such)
> 
>             Andy
> 
> 
> 
> 
> -- 
> 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
> 

Received on Friday, 9 December 2016 16:16:34 UTC