W3C home > Mailing lists > Public > public-rdf-shapes@w3.org > August 2016

Re: comments / questions on the SHACL abstract syntax document

From: Irene Polikoff <irene@topquadrant.com>
Date: Tue, 23 Aug 2016 08:01:05 -0400
To: Iovka Boneva <iovka.boneva@univ-lille1.fr>, <public-rdf-shapes@w3.org>
Message-ID: <D3E1B08D.B4789%irene@topquadrant.com>
I agree with how Iovka described hasValue. It is indeed different from Œiną.

On the second item, I believe that the violation must be produced and that
the spec is clear on the semantics of this constraint:

The existence of the following raises a violation

?s ex:submittedOn ?value1.
?s ex:reproducedOn ?value2.
?value1 >= ?value2


The fact that there is also {?s ex:submittedOn ?value3} that does not meet
the above condition and, thus, doesnąt cause the violation, doesnąt matter.


Irene 

From:  Iovka Boneva <iovka.boneva@univ-lille1.fr>
Date:  Tuesday, August 23, 2016 at 6:25 AM
To:  <public-rdf-shapes@w3.org>
Subject:  comments / questions on the SHACL abstract syntax document
Resent-From:  <public-rdf-shapes@w3.org>
Resent-Date:  Tue, 23 Aug 2016 10:33:22 +0000

    
 1) is a difference between the SHACL abstract syntax and the SHACL
specification
 2) is a potential error in both SHACL abstract syntax and SHACL
specification.
 
 Here above,
 "SHACL abstract syntax" refers to
http://w3c.github.io/data-shapes/shacl-abstract-syntax/ Editor's Draft 23
August 2016
 "SHACL Specification" refers to https://www.w3.org/TR/shacl/  Working Draft
14 August 2016
 
 
 1)
 ISSUE 2 in SHACL abstract syntax Section 5.1.2
http://w3c.github.io/data-shapes/shacl-abstract-syntax/#RDFtermequivalence
 
 The 'hasValue' parameter is not a particular case of the 'in' parameter,
contrary to what is suggested by ISSUE 2.
 As far as I understand the SHACL specification:
 - 'hasValue' tests whether one of the value nodes has the specified value,
and disregards the other value nodes.
 - 'in' tests whether all the value nodes have a value that is included in
the set
 
 The 'hasValue' parameter differs from most of the other parameters with
this regard, which can be misleading to users. So the question whether this
parameter should be treated in the same way as the other parameters is of
independent interest, imho.
 
 
 2)
 In Section 5.1.6 
http://w3c.github.io/data-shapes/shacl-abstract-syntax/#Comparisonwithsiblin
gproperty
 
 The semantics of comparison with specified property is incomplete: it is
undefined in some cases.
 It does not say what happens if there are several value nodes with which to
compare.
 
 For instance, constraint :
 
<IssueShape> sh:property [ sh:predicate ex:submittedOn; sh:lessThan
ex:reproducedOn ] .
 

Graph
 
<issue1> ex:submittedOn "2016-07-08T10:23:45Z"^^xsd:dateTime ;
         ex:reproducedOn "2016-07-08T13:53:00Z"^^xsd:dateTime ;
	 ex:reproducedOn "2016-07-08T09:53:00Z"^^xsd:dateTime .
 

Does the test pass or fail ?
 

As far as I can see, the SHACL specification il also incomplete in this
case.
 
 
 
-- 
Iovka Boneva
Associate professor (MdC) Université de Lille
http://www.cristal.univ-lille.fr/~boneva/
+33 6 95 75 70 25
 
Received on Tuesday, 23 August 2016 12:01:53 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 17:02:43 UTC