W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > August 2003

RE: XML literals

From: <Patrick.Stickler@nokia.com>
Date: Mon, 4 Aug 2003 10:32:17 +0300
Message-ID: <A03E60B17132A84F9B4BB5EEDE57957B5FBC14@trebe006.europe.nokia.com>
To: <connolly@w3.org>
Cc: <bwm@hplb.hpl.hp.com>, <jjc@hpl.hp.com>, <gk@ninebynine.org>, <phayes@ihmc.us>, <w3c-rdfcore-wg@w3.org>, <pfps@research.bell-labs.com>

 

	-----Original Message----- 
	From: ext Dan Connolly [mailto:connolly@w3.org] 
	Sent: Fri 8/1/2003 4:17 PM 
	To: Stickler Patrick (NMP/Tampere) 
	Cc: Brian McBride; Jeremy Carroll; Graham Klyne; ext pat hayes; w3c-rdfcore-wg@w3.org; Peter F. Patel-Schneider 
	Subject: Re: XML literals
	
	

	On Fri, 2003-08-01 at 00:06, Patrick Stickler wrote:
	[...]
	>         
	> Maybe. 
	> 
	>         in 1:1 correspondence with the lexical space.
	> Right.
	
	Hmm... that one gave me pause... but OK.
	
	>         The exact nature of XML values is not specified.
	> 
	> No. This bothers me. Alot.
	
	Really? The exact nature of integers is not specified;
	just various relationships like addition and
	multiplication of them.
	

No. The nature of integers *is* specified, by the relationships such as addition, multiplication, etc.

Perhaps I've misunderstood Pat, but I understood him to be saying that we simply are not going to say anything about the L2V mapping other than it is 1:1 -- i.e. it may very well be that the value space of rdfs:XMLLiteral is rdfs:subClassOf xsd:integer! Since after all, we could posit an L2V mapping that mapped canonical XML fragments onto integers in a 1:1 relationship (theoretically at least).

 

	
	If it bothers you, then feel free to suggest an alternative.
	

	

I did.

	
	We could pick any set that's in 1-1 correspondence
	with the lexical space; e.g. pairs
	        (humpty-dumpty, lexical-value)
	
	or perhaps less churlishly...
	        (http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral <http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral> , lexical-value)
	
	
	> It is our responsibility to define what the values of XML Literals
	> are.
	
	Only inasmuch as required to get the technology deployed.

	

If you mean deployed in a fully system independent, portable manner that facilitates the interchange of RDF expressed knowledge between arbitrary applications where interoperability is based on our specs, then I agree.

But I'm not sure you're saying that. "Deployed" can mean so many things.

	
	
	> It's *our* datatype, and no'one else should have to define it,  or
	> guess.
	
	They don't have to guess; what Pat wrote tells them everything
	they need to know.

I'm an implementor, and *I* am unsure of what the value space of rdfs:XMLLiteral contains, per Pat's recent recommended change. It is clearly *not* the set of lexical forms -- which is the only thing that looks like XML to me. It could be the set of all pumpkins that have ever existed for all I know. 

I expect to operate on values, not lexical forms, and if the datatype definition does not tell me which value I have, given a particular lexical form, the that definition is incomplete and unnacceptable.

		
		> I've never understood the opposition to having a value space
		> consisting of infosets. I wish someone would tell me what significant
		> problem or issue I'm missing...
		
		How to construct an infoset and how to compare them isn't
		specified.
		
		

Thank you. That seems a good reason for not having infosets in the value space.

Still, we do need to define what the value space of rdfs:XMLLiteral is. At the very least, we can simply make rdfs:XMLLiterals self denoting, no?

Patrick
Received on Monday, 4 August 2003 03:39:39 EDT

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:59:32 EDT