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Re: Labels for literals in sh:in enumeration

From: Miika Alonen <miika.alonen@csc.fi>
Date: Thu, 15 Sep 2016 09:45:21 +0300 (EEST)
To: Dimitris Kontokostas <kontokostas@informatik.uni-leipzig.de>
Cc: "public-rdf-sha." <public-rdf-shapes@w3.org>
Message-ID: <1664389732.3142370.1473921921548.JavaMail.zimbra@csc.fi>
Hi, 

Here's another example. Consider you have some legacy XML data we want to transform to RDF. In that case we might have the schema for the XML: 

<?xml version="1.0" encoding="UTF-8"?> 
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:dcterms="http://purl.org/dc/terms/"> 
<xs:element name="RainbowPony" type="RainbowPonyType"/> 
<xs:complexType name="RainbowPonyType"> 
<xs:sequence> 
<xs:element name="HtmlColor"> 
<xs:simpleType> 
<xs:restriction base="xs:string"> 
<xs:enumeration value="#FDD7E4"> 
<xs:annotation> 
<xs:documentation> 
<dcterms:title>Pig Pink</dcterms:title> 
</xs:documentation> 
</xs:annotation> 
</xs:enumeration> 
<xs:enumeration value="#800080'"> 
<xs:annotation> 
<xs:documentation> 
<dcterms:title>Purple</dcterms:title> 
</xs:documentation> 
</xs:annotation> 
</xs:enumeration> 
</xs:restriction> 
</xs:simpleType> 
</xs:element> 
</xs:sequence> 
</xs:complexType> 
</xs:schema> 

And we want to create RDF representation for the data, say: 

_:n1 ex:htmlColor '#FDD7E4' . 

And for validating that we could then create a shape: 

ex:InExampleShape 
a sh:Shape ; 
sh:targetNode ex:RainbowPony ; 
sh:property [ 
sh:predicate ex:htmlColor ; 
sh:in ('#FDD7E4' '#800080') ; 
] . 

The issue was that this representation is missing the option to annotate the literal values. You can of course argue that the color representation should be a Resource: (color:Pink ex:htmlColor '#FDD7E4') but i dont think its reasonable to create resources for all literal values just that you can document those values in the schema. 

- Miika 


From: "Miika Alonen" <miika.alonen@csc.fi> 
To: "Dimitris Kontokostas" <kontokostas@informatik.uni-leipzig.de> 
Cc: "public-rdf-sha." <public-rdf-shapes@w3.org> 
Sent: Wednesday, 14 September, 2016 12:06:15 
Subject: Re: Labels for literals in sh:in enumeration 

Hi, 

Listing the values and labels to the same list, for example: 

sh:in (' #FDD7E4 ' 'Pig Pink' ' #800080 ' 'Purple'); 

would mean that 'Pig Pink' and 'Purple' are also a valid values for the predicate. This would be very odd and not very explicit if you dont know what to expect from the enumerations. 

All i can think of (without adding something to the SHACL syntax) would be to include labels to separate resources describing the literals: 

_:x1 rdf:value '#FDD7E4' . 
_:x1 rdfs:label 'Pig Pink'@en . 
_:x1 rdfs:label 'Vaaleanpunainen'@fi . 

... but then the labels would be kind of off the specification that wouldnt support generic form generation. 

- Miika 


From: "Dimitris Kontokostas" <kontokostas@informatik.uni-leipzig.de> 
To: "Miika Alonen" <miika.alonen@csc.fi> 
Cc: "public-rdf-sha." <public-rdf-shapes@w3.org> 
Sent: Wednesday, 14 September, 2016 10:40:56 
Subject: Re: Labels for literals in sh:in enumeration 

Hello Miika, 
you can have it like 
sh:in ( 1 333 true "string" "lang string"@en "2"^^xsd:unsignedInteger ex:A ) 
and SHACL will check if your value is in this list 

if your rdf nodes in the sh:in list are valid, i.e. there is no "a"^^xsd:int SHACL engnes (the ones based on SPARQL at least) will work correctly 

On Wed, Sep 14, 2016 at 9:01 AM, Miika Alonen < miika.alonen@csc.fi > wrote: 



Hi all, 

What would be the best way to include labels to sh:in for literals? Using literals instead of resources is reasonable in some use cases. 

For example you might want to use literals for HTML colors and labels for the drop down menu: 
ex:InExampleShape
	a sh:Shape ;
	sh:targetNode ex:RainbowPony ;
	sh:property [
		sh:predicate ex:htmlColor ;
		sh:in (' #FDD7E4 ' ' #800080 ') ;
	] . 

instead of: 





BQ_BEGIN


sh:in ( ex:Pink ex:Purple ) ... 
... and something like ... ex:Pink rdf:value ' #FDD7E4 ' . 
There is of course many ways to model this but in case you need to use literals for simplicity the could be something like enumNames that is proposed to JSON Schema v5: https://github.com/json-schema/json-schema/wiki/enumNames-(v5-proposal) 

Best Regards, 
Miika Alonen 

CSC - IT Center for Science 
miika.alonen@csc.fi 


BQ_END




-- 
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 Thursday, 15 September 2016 06:45:57 UTC

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