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a low-impact datatypes proposal: rdfs:format

From: Dan Connolly <connolly@w3.org>
Date: 03 Oct 2002 17:33:45 -0500
To: w3c-rdfcore-wg@w3.org
Message-Id: <1033684425.13756.813.camel@dirk>

I suggest that what folks really need is
to be able to write

 my:age rdfs:format xsdt:integer.

in their schema in such a way standard
tools will recognize

 :jenny my:age "10".

as 'good' and

 :jenny my:age "young".

as 'bad'.

So I propose just one new property, rdfs:format.

Specification/model theory: if DDD is one
of the XML Schema built-in datatypes
http://www.w3.org/TR/xmlschema-2/#built-in-datatypes
and
	PPP rdfs:format DDD
	XXX DDD LLL
then LLL is in the lexical space of that
datatype.

That's it.

* no RDF/xml syntax changes
* no abstract syntax changes
* one term added to the RDF schema spec
* a brief explanation ala the one
  above in the primer; a few paragraphs
  in rdf-concepts
* low impact on cc/pp
  (just change rdfs:range to rdfs:format
  in a few places in the schema; zero
  changes to instances)
* easy to use with the dublin core vocab,
  RSS, etc.
* no impact on any of the existing
  working code I'm aware of
* straightforward to implement, given
  a piece of code that checks lexical
  forms of XML Schema dataypes, 80% of
  which can be done with regex libraries.
* a handful of test cases: for each
  datatype, few test cases that
  show values that aren't allowed.
* no core model theory changes;
  a brief explanation ala the above
  of rdfs:format

I'm quite concerned that the rdf:datatype proposal
is too complex to deal with in a timely manner;
The sorts of questions Graham asks in his 30Sep
message...
  http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Sep/0370.html
could take quite a while to sort out.

I think something as complex as this medium-range proposal from HP
is *crazy* at this point; we really expect users to understand
a new magic kind of file-scoped triple? We really expect to
get all this abstract syntax of integers/dates stuff right?
http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Oct/0019.html

(for reference: an enumeration of the datatypes
and some notes on test cases from an earlier design...
http://www.w3.org/2000/10/swap/util/datatypes.n3)

-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
Received on Thursday, 3 October 2002 18:33:24 EDT

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