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RDF testcase rdfms-rdf-names-use/test-025.rdf

From: Chet Murthy <chet@watson.ibm.com>
Date: Mon, 02 Dec 2002 13:33:31 -0500
Message-Id: <200212021833.gB2IXVKT001835@nautilus-chet.watson.ibm.com>
To: Chet Murthy <chet@watson.ibm.com>
cc: www-rdf-interest@w3.org, Dave.Beckett@bristol.ac.uk


[I'm not sure this is the right place to send a note like this -- if
not, please advise.]

I'm starting down the RDF road, writing tools, etc, and am at the
point of writing tools which will pass the testcases in
RDF-TESTCASES.  I was beavering down this path, when I got derailed by
the subject testcase.

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
  <rdf:Description rdf:about="http://example.org/node1">
    <rdf:li rdf:resource="http://example.org/node2"/>
  </rdf:Description>
</rdf:RDF>

Now, I also looked at the RDF issues list, and as far as I can tell,
it stipulates there that the above RDFXML is in error.

It seems to me that the above is equivalent to


<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
         xmlns:eg="http://example.org/">
  <eg:node1>
    <rdf:li rdf:resource="http://example.org/node2"/>
  </eg:node1>
</rdf:RDF>

and this latter form is extremely similar to
(rdf-containers-syntax-vs-schema/test003.rdf)

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
         xmlns:foo="http://foo/">
  <foo:Bar>
    <rdf:li>1</rdf:li>
    <rdf:li>2</rdf:li>
  </foo:Bar>
</rdf:RDF>

which is equivalent to (rdf-containers-syntax-vs-schema/test003.nt)

_:bar <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>  <http://foo/Bar> .
_:bar <http://www.w3.org/1999/02/22-rdf-syntax-ns#_1> "1" .
_:bar <http://www.w3.org/1999/02/22-rdf-syntax-ns#_2> "2" .

The upshot, it seems to me, is that the rdf:li property, anywhere,
_forces_ a per-node counter to be incremented, in a manner which
assigns to each rdf:li property an ascending ordinal name.

The only explanation I can see for arguing that rdf:li, as a property
of an "rdf:Description" node, is that such a node is intrinsically
_different_ from the abbreviation in which its rdf:type is converted
into a namespaced XML tag, (e.g., "eg:node1" above).

So, in sum, I don't understand why the Ntriple output for the first
RDFXML is

<http://example.org/node1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#li> <http://example.org/node2> .

rather than

<http://example.org/node1> <http://www.w3.org/1999/02/22-rdf-syntax-ns#_1> <http://example.org/node2> .

Cheers,
--chet--

================================================================

Issue rdfms-rdf-names-use: Illegal or unusual use of names from the RDF namespace

raised Thu, 14 Jun 2001 by Jeremy Carroll

Summary: Clarify the legality of the use of names from the RDF namespace, e.g. can rdf:Bag be used as a property or can rdf:Description be used as a property attribute etc.

Resolution: On 30th November 2001, the RDFCore WG:

    * Resolves that the use of rdf:RDF, rdf:ID, rdf:about, rdf:resource, rdf:bagID, rdf:parseType, rdf:aboutEach and rdf:li except as reserved names as specified in the grammar is an error.
    * resolves that test case http://www.w3.org/2000/10/rdf-tests/rdfcore/rdf-containers-syntax-vs-schema/test005.rdf be obsoleted
    * resolves that a copy of that test case be created as an error test

At the February face to face meeting, the WG futher resolved:

The WG reaffirmed its decision not to restrict names in the RDF namespaces which are not syntactic. The WG decided that an RDF processor SHOULD emit a warning when encountering names in the RDF namespace which are not defined, but should otherwise behave normally.

And that specifically:

  <rdf:Description> 
    <rdf:foo>foo</rdf:foo>
   </rdf:Description> 

is equivalent to:

 _:a <rdf:foo> "foo" .
Received on Monday, 2 December 2002 22:10:37 GMT

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