W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > February 2002

Re: Parser mods to support rdf:dtype and rdf:lform

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Fri, 15 Feb 2002 13:58:55 +0000
Message-Id: <5.1.0.14.0.20020215134844.00a75bc0@0-mail-1.hpl.hp.com>
To: Patrick Stickler <patrick.stickler@nokia.com>, RDF Core <w3c-rdfcore-wg@w3.org>
At 13:16 15/02/2002 +0200, Patrick Stickler wrote:
>On 2002-02-15 12:10, "ext Brian McBride" <bwm@hplb.hpl.hp.com> wrote:
>
> > At 11:04 15/02/2002 +0200, Patrick Stickler wrote:
> > [...]
> >>    <dc:date rdf:value="2002-02-14" rdf:dtype="&xsd;date"/>
> >
> > Am I right that under the current proposal this can be more compactly 
> written:
> >
> >  <dc:date xsd:date="2002-02-14"/>
>
>Yes and no. It is more compact, but is less local (thus it
>is not exactly an equivalent variant of the doublet idiom).

true - its a different triple structure as Dave said.  I'm not clear what 
value the greater "locality" brings.


>In this case, it is not clear from the RDF that xsd:date is a
>datatype. It could be any kind of property at all.

Hmmm, I expect datatype aware implementations to recognise that xsd:date is 
a datatype.

>  It has
>no more datatyping clarity to the parser than

I don't expect the parser to care whether its a datatype or not.


>    <dc:date foo:bar="2002-02-14"/>
>
>And it is unclear, if e.g xml:lang is specified, whether
>the value of xsd:date or foo:bar is the actual literal
>value

I don't know what you mean by the "actual" literal value.  However, I don't 
believe there is any ambiguity in the triple structure.

>of the dc:date property or just some extra attribution
>of the bNode. Thus, schema knowledge would be required
>by the parser (not just pre-defined automatic statements
>in the spec) to know for sure that xsd:date or foo:bar
>should be treated as rdf:value.

I don't see that at all.  The transform to triples is schema independent.


>And one would not, I think, expect xml:lang to apply to
>all attributes of the element

Why not?

>-- or really to any of
>the attributes, but rather only the content of the element,
>and it's just a trick of rdf:value that the content can
>be hidden (contracted) into an attribute.
>
>If I have
>
>  <dc:title rdf:value="Foo" xml:lang="en" x:scope="237a87"/>
>
>we're saying that "Foo" is English, but not "237a87".

Where is that specified?

[snip]

>I admit that it's a handy form of expression, but these
>issues have to be resolved before we're completely
>done, I think.

I see no issues.


> > which would require no change to the parsers?
>
>Correct, in that the required bNode is generated.
>Apologies for missing this in my earlier examples.
>
>Though, as pointed out above, proper attachment of xml:lang
>to the literal either requires schema knowledge or results
>in over-attachment to all attributes.

That kinda depends on what you mean by proper.  In my view xml:lang can be 
handled properly without schema knowledge, and in fact it would be highly 
improper to require it.  Parsers parse.

Brian
Received on Friday, 15 February 2002 09:00:40 EST

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:45:12 EDT