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Re: Markup questions: html/body, datatype="", double predicates

From: Mark Birbeck <mark.birbeck@webbackplane.com>
Date: Mon, 15 Dec 2008 06:35:20 -0500
Message-ID: <ed77aa9f0812150335v4df340a7t2d44188348ed4d50@mail.gmail.com>
To: "Ivan Herman" <ivan@w3.org>
Cc: "Toby A Inkster" <tai@g5n.co.uk>, public-rdfa@w3.org, RDFa <public-rdf-in-xhtml-tf@w3.org>
Hi Ivan,

Toby is right here, that a shorthand for expressing XML literals (and
consequently turning off recursion) is to have no @datatype value, and to
have non-text child nodes. For example, the following generates only one
triple:

  <div property="my:template">
    <span property="foaf:name">${name}</span>
  </div>

and is equivalent to:

  <div property="my:template" datatype="rdf:XMLLiteral">
    <span property="foaf:name">${name}</span>
  </div>

Note that the former doesn't require the RDF namespace to be declared.

If we want the 'nested' predicates to be processed, we have a couple of
choices. If the text nodes of all child elements will appear as part of the
value of the predicate, then we can force a non-XMLLiteral datatype. In this
example, we force the data to be a plain literal:

  <div property="foaf:name" datatype="">
    <span property="foaf:givenname">Ivan</span>
    <span property="foaf:surname">Herman</span>
  </div>

Which generates:

  <> foaf:name "Ivan Herman" .
  <> foaf:givenname "Ivan" .
  <> foaf:surname = "Herman" .

Alternatively, if there is no relationship between the document hierarchy
and the values, then we could use @content:

  <div property="foaf:name" content="Ivan Herman">
    <span property="foaf:surname">Herman</span>,
    <span property="foaf:givenname">Ivan</span>
  </div>

This allows recursion to continue, but also sets the value of foaf:name
independently of any child elements.

Regards,

Mark

On Mon, Dec 15, 2008 at 5:17 AM, Ivan Herman <ivan@w3.org> wrote:

>
>
> Toby A Inkster wrote:
> >
> > Ivan Herman wrote:
> >
> >> Ben, Mark, Michael, others: what do you think?
> >
> > My understanding of the syntax specification is that conforming
> > implementations must generate both triples in your example.
> >
>
> I begin to yield to the fact that I have a bug in distiller on this...
> But I would still want to have a formal confirmation before I change my
> code!
>
>
> > Another test which I think is missing from the suite is:
> >
> > <div property="ex:foo">
> >   <span property="ex:bar">bar</span>
> > </div>
> >
> > should generate an XMLLiteral for ex:foo, but there should be no ex:bar
> > triple.
>
> Yes, you are right! That is another case to consider through a proper test.
>
> Thanks
>
> Ivan
>
> >
> > Also, may I draw attention to this again:
> >
> http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2008Dec/0012.html
> >
> >
>
> --
>
> Ivan Herman, W3C Semantic Web Activity Lead
> Home: http://www.w3.org/People/Ivan/
> PGP Key: http://www.ivan-herman.net/pgpkey.html
> FOAF: http://www.ivan-herman.net/foaf.rdf
>



-- 
Mark Birbeck, webBackplane

mark.birbeck@webBackplane.com

http://webBackplane.com/mark-birbeck

webBackplane is a trading name of Backplane Ltd. (company number
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Received on Monday, 15 December 2008 11:35:59 UTC

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