- From: Holger Knublauch <holger@topquadrant.com>
- Date: Sat, 10 Dec 2016 11:23:19 +1000
- To: "Peter F. Patel-Schneider" <pfpschneider@gmail.com>, Dimitris Kontokostas <kontokostas@informatik.uni-leipzig.de>
- Cc: "public-rdf-sha." <public-rdf-shapes@w3.org>
On 10/12/2016 2:44, Peter F. Patel-Schneider wrote: > The wording about value nodes at the beginning of Section 4 in the document > needs to be tightened. The document doesn't even define the notion of > reachability. Do you have specific input to address that? Thanks, Holger > > peter > > > On 12/08/2016 11:49 PM, Dimitris Kontokostas wrote: >> Thank you for your feedback Peter, >> would something like the following wording resolve this issue? >> Validation results may have a <a>SHACL property path</a> as value for the >> property <code>sh:resultPath</code> that represents the <a>property path</a> >> from the focus node to the value node. >> >> On Fri, Dec 9, 2016 at 6:21 AM, Holger Knublauch <holger@topquadrant.com >> <mailto:holger@topquadrant.com>> wrote: >> >> I have raised ISSUE-217 for this. >> >> https://www.w3.org/2014/data-shapes/track/issues/217 >> <https://www.w3.org/2014/data-shapes/track/issues/217> >> >> Holger >> >> >> >> On 9/12/2016 11:29, Peter F. Patel-Schneider wrote: >> >> ISSUE<<<<<<<<<<<<<<<<<< >> >> The requirements for values of sh:resultPath in validation results are >> impossible to achieve, poorly defined, contradictory, and problematic for >> applications that consume validation reports.. >> >> ISSUE<<<<<<<<<<<<<<<<<< >> >> >> 3.4.2.2 Path (sh:resultPath) >> Validation results may have a value for the property sh:resultPath >> pointing >> at a well-formed property path starting with the given sh:focusNode. For >> results produced by a property constraint, this path is always >> identical to >> either the sh:predicate or sh:path of the constraint. >> >> >> A property path is a "possible route in a graph between two graph nodes". >> There is no definition of route to be found in the document. It is >> thus not >> possible to point to a property path, well-formed or not. >> >> The values of sh:predicate and sh:path in shapes graphs are SHACL property >> paths. As objects of triples in a graph these values are nodes in the >> graph, and certainly not routes of any kind. >> >> Identity of RDF terms is not defined in RDF, so it is not completely clear >> what the second sentence in the description above means. The only >> reasonable interpretation appears to be that value of sh:resultPath is the >> same as the object of the sh:predicate or sh:path triple, which >> implies that >> validation results will contain nodes taken from shapes graphs. This is >> contradictory as nodes are not paths. >> >> This is also problematic for applications that consume validation >> reports as >> it requires the ability to take a blank node from one graph and find the >> same blank node in another graph, which is not always possible in RDF. >> >> >> This is yet another case of malformed descriptions in the document. The >> document needs to be changed to provide a well-formed description for the >> value of sh:resultPath in validation results. A complete examination >> of the >> document by a competent member of the working group is needed to find and >> eliminate other similar problems in the document. >> >> >> Peter F. Patel-Schneider >> Nuance Communications >> >> >> >> >> >> >> >> >> -- >> 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 Saturday, 10 December 2016 01:23:56 UTC