Fwd: Review RDFa LC Primer & Lite documents: relevant to ISSUE-119 (@resource in RDFa Lite instead of @about)

Begin forwarded message:
[snip]

> Resent-From: public-rdfa-wg@w3.org
> From: Guus Schreiber <guus.schreiber@vu.nl>
> Subject: Fwd: Review RDFa LC Primer & Lite documents
> Date: January 18, 2012 18:25:22 GMT+01:00
> To: public-rdfa-wg@w3.org
> Archived-At: <http://www.w3.org/mid/4F170082.4040705@vu.nl>
> List-Id: <public-rdfa-wg.w3.org>
> 
> Manu, all,
> 
> Below some comments on the RDFa Lite and Primer documents. They're mainly editorial, I think.
> 
> Best,
> Guus
> 

[snip]

> 
> 1. The social network example in Sec 3.2 contains three blank nodes,
> despite the fact that you stated a few lines before that this is not
> good practice.  I suggest to include an "about" attribute for Bob/Eve/Manu.
> 


The example Guus is referring to is:

<div vocab="http://xmlns.com/foaf/0.1/">
   <ul>
      <li typeof="Person">
        <a href="http://example.com/bob/">Bob</a>
      </li>
      <li typeof="Person">
        <a href="http://example.com/eve/">Eve</a>
      </li>

Indeed, the following would be better:

<div vocab="http://xmlns.com/foaf/0.1/">
   <ul>
      <li about="#bob" typeof="Person">
        <a href="http://example.com/bob/">Bob</a>
      </li>
      <li about="#eve" typeof="Person">
        <a href="http://example.com/eve/">Eve</a>
      </li>

However, a few lines below, when building up the example, we want to add a property that aligns it with the 'upper' layers; the current primer has:

<div vocab="http://xmlns.com/foaf/0.1/" about="#me">
   <ul>
      <li property="knows" typeof="Person">
        <a href="http://example.com/bob/">Bob</a>
      </li>
      <li property="knows" typeof="Person">
        <a href="http://example.com/eve/">Eve</a>
      </li>

but, if we added #about, then we'd get

<div vocab="http://xmlns.com/foaf/0.1/" about="#me">
   <ul>
      <li property="knows"  about="#bob" typeof="Person">
        <a href="http://example.com/bob/">Bob</a>
      </li>
      <li property="knows"  about="#eve" typeof="Person">
        <a href="http://example.com/eve/">Eve</a>
      </li>

which is _wrong_ with what we want to have. Indeed, typeof sticks with about, and that becomes the subject for @property which is not what we want. On the other hand, 

<div vocab="http://xmlns.com/foaf/0.1/" about="#me">
   <ul>
      <li property="knows" resource="#bob" typeof="Person">
        <a href="http://example.com/bob/">Bob</a>
      </li>
      <li property="knows" resource="#eve" typeof="Person">
        <a href="http://example.com/eve/">Eve</a>
      </li>

does exactly what we want, because resource remains an object for property...

If we want to stick to RDFa Lite at this part of the primer, which is probably a good idea, then we have a problem...

Just food for thought.

Ivan


----
Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
FOAF: http://www.ivan-herman.net/foaf.rdf