W3C home > Mailing lists > Public > public-rdf-wg@w3.org > March 2011

Re: RDF-ISSUE-12 (String Literals): Reconcile various forms of string literals (time permitting) [Cleanup tasks]

From: Pat Hayes <phayes@ihmc.us>
Date: Mon, 7 Mar 2011 16:25:25 -0600
Cc: antoine.zimmermann@insa-lyon.fr, public-rdf-wg@w3.org
Message-Id: <D5F8F46E-EDAE-4D92-A0E7-2EF506C03F30@ihmc.us>
To: Andy Seaborne <andy.seaborne@epimorphics.com>

On Mar 7, 2011, at 2:45 PM, Andy Seaborne wrote:

> 
> 
> On 07/03/11 17:26, Antoine Zimmermann wrote:
>> Le 07/03/2011 09:40, Andy Seaborne a écrit :
>>> rdf:PlainLiteral should never appear in RDF as a datatype.
>>> 
>>> The literal should have been written in normal RDF form.
>>> 
>>> http://www.w3.org/TR/rdf-plain-literal/
>>> [[ Sec 4:
>>> Therefore, typed literals with rdf:PlainLiteral as the datatype are
>>> considered by this specification to be not valid in syntaxes for RDF
>>> graphs or SPARQL.
>>> 
>>> To implement this design and provide this interoperability, applications
>>> that employ this datatype MUST use plain literals (instead of
>>> rdf:PlainLiteral typed literals) whenever a syntax for plain literals is
>>> provided, such as in existing syntaxes for RDF graphs and SPARQL results.
>>> ]]
>>> 
>> 
>> Do we want to include this in RDF?
> 
> The text?  I suppose so because it's in a spec somewhere so we ought to consolidate.
> 
> Best advice might be that parsers (input) are required to convert to plain literal form, so the rdf:PlainLiteral does not appear as a syntactic form.
> 
>> RDF says:
>> 
>> """Everything of the form "blabla"^^someURI can be the object of a
>> triple."""
>> 
>> If we include rdf:plainLiteral in the spec of RDF, we then say:
>> 
>> """Everything of the form "blabla"^^someURI can be the object of a
>> triple *except* if someURI = rdf:plainLiteral."""
> 
> The only reason it starts "rdf:" as far as I can see is that RIF and OWL2 couldn't agree to put in one namespace or the other so they encroached on RDF.  That's not a good reason.
> 
>> Which sounds weird. Or maybe this is optional, just to be considered for
>> use with D-entailment?
> 
> And explaining that "blabla"^^rdf:plainLiteral is an illegal PlainLiteral, that a string (lexicial form) has to have a @ in it but it does not form part of the string (value) isn't weird?!!

This is what I meant when I said that rdf:plainLIteral is a crock because it had to fit around the existing specs. We have an opportunity to do this better. 

Pat

> 
> 	Andy
> 
> 
> 

------------------------------------------------------------
IHMC                                     (850)434 8903 or (650)494 3973   
40 South Alcaniz St.           (850)202 4416   office
Pensacola                            (850)202 4440   fax
FL 32502                              (850)291 0667   mobile
phayesAT-SIGNihmc.us       http://www.ihmc.us/users/phayes
Received on Monday, 7 March 2011 22:26:15 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 17:04:03 UTC