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Re: literals in lists.

From: Ivan Herman <ivan@w3.org>
Date: Wed, 25 Jul 2007 10:51:19 +0200
Message-ID: <46A70F07.30507@w3.org>
To: Garret Wilson <garret@globalmentor.com>
Cc: Sandro Hawke <sandro@w3.org>, Semantic Web <semantic-web@w3.org>
Garret,

I think what Sandro refers to is the difference between the RDF model
and the particular syntax called RDF/XML.

1- in the RDFS specification, the range of rdfs:first is
rdfs:Resource[1]. Ie, everything, including literals.

2- in RDF/XML there is no problem in spelling out a list using literals

<rdfs:List>
   <rdfs:first>Bla bla bla</rdf:first>
   <rdfs:rest>
      <rdfs:List>
        <rdsf:first>Bla again</rdfs:first>
        <rdfs:rest rdf:resource=".....nil"/>
      </rdfs:List>
   </rdfs:rest>
</rdfs:List>

3- The particular syntactic simplification rule in RDF/XML using
@rdf:parseType has indeed the limitation of referring to resources only,
ie, one cannot write:

  <some:property rdf:parseType="Collection">
    "Bla bla bla" "Bla again"
  </some:property>

4- Other serializations of RDF might be more accommodating. Ie, in
Turtle, it is perfectly o.k. to write

<> some:property ("Bla bla bla" "Bla again").

I realize that RDF/XML is a bit heavy for this (too:-), but I hope it
explains what Sandro meant...

Ivan

[1] http://www.w3.org/TR/rdf-schema/#ch_first

Garret Wilson wrote:
> 
> Sandro,
> 
> Sandro Hawke wrote:
>> To be clear, an rdf:List can have literals, it's just that
>> parseType=Collection cannot be used with such lists.
>>
>> I'm curious why you prefer rdf:value for this workaround instead of
>> owl:sameAs....        
> 
> Can you explain this some more? I'm always on the lookout to improve my
> kludges with better kludges... ;)
> 
> Garret
> 

-- 

Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf

Received on Wednesday, 25 July 2007 08:51:21 GMT

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