Re: Yet another instanceof test

Hi Ivan,

We seem to be going over a debate we have already had. [1]


> Looking at the (approved) pair of test cases #0049 and #0050 you are
> right if the usage pattern is:
>
> <html>
>    <head  instanceof="foaf:PersonalProfileDocument">
>
> (in which case my submitted test case is wrong!)
>
> However, I must admit that _my_ usage pattern has always been
>
> <html instanceof="foaf:PersonalProfileDocument">
>   <head>
>   ...

I don't know what you mean by "has always been"; in the long thread
that we had on this [1], all of my examples use <head>, and I don't
see any other examples that come from anyone else.


> which is actually quite correct and the situation
>
> <html instanceof="foaf:PersonalProfileDocument">
>    <head>
>      <link rel="foaf:maker"...
>
> would not yield any unexpected triples.

No, I didn't say it would. :)

But if, in your example, an author were to place @instanceof onto the
<head> element, that _would_ change the meaning of the "foaf:maker"
statement, unless we inhibit the bnode in some way. The proposal is
obviously that this is best done by having a default value for @about.

(This is all in the previous thread. [2])


> [snip]
>
> [I've cut out all of the points relating to processing sequence and @instanceof,
> since they can be discussed separately.]


> Well, reading through my own lines above, I wonder if
>
> - simplify @instanceof (in particular, change test #0050, no blank node!)
> - put the default on <html>
>
> is not a cleaner approach altogether.

Whether or not that would be a 'simplification', we can keep for
another thread. :)

But the main point is that putting @about="" on <html> doesn't solve
the very specific problem that I raised a few weeks ago, and that we
had a long thread of discussion about.

The discussion begins here [1], and note that all of the examples use
<head>. In particular, see the main motivation for using <head> rather
than <html> [2]. Also, see Ben's comments that as it happens we had
agreed a long time ago on the use of @about="" for <head>, but that he
couldn't find the reference [3]. And finally, see your own reply that
you were happy with the location of the @about being the <head>
element [4, 5].

Regards,

Mark

[1] <http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2007Oct/0000.html>
[2] <http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2007Oct/0004.html>
[3] <http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2007Oct/0022.html>
[4] <http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2007Oct/0026.html>
[5] <http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2007Oct/0031.html>

-- 
  Mark Birbeck, formsPlayer

  mark.birbeck@formsPlayer.com | +44 (0) 20 7689 9232
  http://www.formsPlayer.com | http://internet-apps.blogspot.com

  standards. innovation.

Received on Monday, 29 October 2007 14:19:12 UTC