On 2021-02-25 9:44 am, [email protected] wrote:
The SHACL-AF spec
<https://w3c.github.io/shacl/shacl-af/#minus> contains a definition
for a property called sh:minus, but I don't think my brain is able to
parse it properly. Some examples might help, but the only one I've
been able to find anywhere is in Example 3 of this tutorial
<https://www.topquadrant.com/graphql/values.html#examples-family>,
where sh:this is used as the object of sh:minus.
What I want to do is define a property shape that infers a list of
values that is calculated by taking all the values of another property
shape -- call it ex:includes -- and removing all the values of a third
property shape -- call it ex:excludes. But I can't seem to write a
valid sh:values statement that does this.
Is sh:minus even the right property to use for this? If so, what is
the proper syntax? For what it's worth, this was one of my attempts:
sh:values [
sh:nodes [
sh:path ex:includes;
] ;
sh:minus ex:excludes;
] ;
sh:minus takes any node expression and will simply compute the nodes
resulting from sh:nodes and then remove the nodes resulting from sh:minus.
Did you try
sh:values [
sh:nodes [ sh:path ex:includes ] ;
sh:minus [ sh:path ex:excludes ];
] ;
The way you have written it would just exclude the property ex:excludes
itself, because that's a constant term node expression
https://w3c.github.io/shacl/shacl-af/#node-expressions-constant
For the geeks here is the implementation of sh:minus
public ExtendedIterator<RDFNode> eval(RDFNode focusNode,
NodeExpressionContext context) {
Set<RDFNode> sans = minus.eval(focusNode, context).toSet();
return getInput().eval(focusNode, context).filterDrop(n ->
sans.contains(n));
}
Holger
--
You received this message because you are subscribed to the Google
Groups "TopBraid Suite Users" group.
To unsubscribe from this group and stop receiving emails from it, send
an email to [email protected]
<mailto:[email protected]>.
To view this discussion on the web visit
https://groups.google.com/d/msgid/topbraid-users/ba2904a6-242d-4c9c-8ad3-ad334edfd5e1n%40googlegroups.com
<https://groups.google.com/d/msgid/topbraid-users/ba2904a6-242d-4c9c-8ad3-ad334edfd5e1n%40googlegroups.com?utm_medium=email&utm_source=footer>.
--
You received this message because you are subscribed to the Google Groups "TopBraid
Suite Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/topbraid-users/551b2dea-a35d-c1a9-d84b-a7059371c777%40topquadrant.com.
