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Re: how does existing RDF software handle this datatypes test?

From: Ora Lassila <daml@lassila.org>
Date: Wed, 30 Jan 2002 20:37:53 -0500
Message-Id: <a05101000b87e4eca8055@[192.168.1.128]>
To: Dan Connolly <connolly@w3.org>
Cc: RDF Interest <www-rdf-interest@w3.org>, RDF Logic <www-rdf-logic@w3.org>
Dan,

At 11:03 -0600 2002-01-30, Dan Connolly wrote:
>If you have any sort of RDF API or query language or
>any sort of software in which this question can be posed,
>would you please ask your implementation and tell
>us its answer right now?

In Wilbur (http://purl.org/net/wilbur/), this is what happens ("?" is 
the Lisp listener prompt):

Welcome to Macintosh Common Lisp Version 4.3.1!
? (in-package :wilbur)
#<Package "WILBUR">
? (setf *db* (make-instance 'db :emptyp t))
#<db size 0 #x184D28FE>
? (load-db (make-url "http://www.w3.org/2000/10/swap/test/dt10-premise.rdf"))
#<db size 3 #x184DD9D6>
!"http://www.w3.org/2000/10/swap/test/dt10-premise.rdf"
nil
? (add-namespace "premise" 
"http://www.w3.org/2000/10/swap/test/dt10-premise.rdf#")
"premise"
? (db-triples *db*)
(#<triple #<node #x184E0F06> !rdf:type !premise:Film #x184E139E>
  #<triple #<node #x184E0F06> !dc:title "10" #x184E1EE6>
  #<triple !premise:mary !ex:age "10" #x184E236E>)
? (query nil !dc:title nil)
(#<triple #<node #x184E0F06> !dc:title "10" #x184E1EE6>)
t
? (triple-subject (first *))
#<node #x184E0F06>
? (all-values * '(:seq !dc:title (:inv !ex:age)))
nil
?

Why? Because Wilbur implements literals as Common Lisp strings, hence 
two strings read in at different times are not EQ which is what the 
query language expects of the nodes in the graph. I suppose this 
could be fixed rather easily.

Regards,

	- Ora

-- 
Ora Lassila  mailto:daml@lassila.org  http://www.lassila.org/
Research Fellow, Nokia Research Center
Received on Wednesday, 30 January 2002 20:38:29 GMT

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