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Re: Use of "about" in RDF-Schema?

From: Ralph R. Swick <swick@w3.org>
Date: Wed, 13 Oct 1999 14:44:01 -0400
Message-Id: <3.0.5.32.19991013144401.02d4eb80@127.0.0.1>
To: Karsten Tolle <tolle@csi.forth.gr>
Cc: www-rdf-comments@w3.org
At 11:05 AM 9/30/1999 +0300, Karsten Tolle wrote:
http://lists.w3.org/Archives/Public/www-rdf-comments/1999JulSep/0050

>fist of all there seems to be an error in the "Compact XML Serialization" 
>of the "RDF-Schema":
>
>...
><rdf:Property ID="label"
>        rdfs:Label="label"
> ...
>
>it should be: rdfs:label="label"
>(this error is also in the machine readable description of the RDF schema)

Yes, you are correct; "rdfs:Label" is misspelled in Appendix A of
http://www.w3.org/TR/PR-rdf-schema.

>But my main question is about the way the attribute "about" is used in the
>RDF-Schema Compact XML Serialization. 
>
>e.g. ... <rdfs:Class about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement" ...
>
>For me this would mean: The attribute (in this case "about") will inherit the
>namespace of the tag name. So, we would have rdfs:about and not 
>rdf:about.  

Correct again.  There are two typos in this description; it should read:

  <rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement"
        rdfs:label="Statement"
        rdfs:comment="This represents the set of reified statements.">
    <rdfs:subClassOf rdf:resource="#Resource"/>
  </rdfs:Class>

(the namespace prefixes on the label and comment attributes could
be omitted)

The missing namespace prefix error also appears in the descriptions
of http://www.w3.org/1999/02/22-rdf-syntax-ns#Bag,
http://www.w3.org/1999/02/22-rdf-syntax-ns#Seq, and
http://www.w3.org/1999/02/22-rdf-syntax-ns#Alt

>On the other hand there is:
>
>... <rdfs:Class rdf:ID="Literal" ...
>
>Is there any reason to treat the attributes "ID" and "about" in different ways?

No, just a mistake.

You also noted (in direct mail to me) another error in this section
that appears in both the Basic XML Serialization and the Compact XML
Serialization text

 <rdf:Description ID="Property" ...
 <rdfs:Class rdf:ID="Property" ...

These declare http://www.w3.org/TR/1999/PR-rdf-schems-19990303#Property
but Property is intended to be defined [only] in the
http://www.w3.org/1999/02/22-rdf-syntax-ns# namespace (see Section 2.2.2).

They should instead read:

 <rdf:Description about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"
 ...

and

 <rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"
 ...

Thank you for pointing all these out.  I have added all this to the
errata page http://www.w3.org/TR/PR-rdf-schema/errata

-Ralph
Received on Wednesday, 13 October 1999 14:45:58 GMT

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