Re: [whatwg] A Selector-based metadata proposal (was: Annotating structured data that HTML has no semantics for)

2009-05-17 Thread Eduard Pascual
First of all, thanks for the time taken to review the document and to
post your feedback. I truly appreciate it.

On Sat, May 16, 2009 at 2:12 PM, Toby A Inkster m...@tobyinkster.co.uk wrote:
 In part 0.1 you include some HTML and some RDF triples that you'd like to
 mark up in the HTML and conclude that RDFa is incapable of doing that
 without adding extra wrapper elements.

 While adding redundant wrapper elements and empty elements is occasionally
 needed in RDFa (and from what I can tell, the microdata approach is even
 worse at this), the example you give doesn't require any.
I think I already stated this somewhere, but it never hurts to state
it again: as any human, I can make mistakes; and my knowledge about
RDF, RDFa, and even CSS, is definitely far from perfect. So, thanks
for your post that has actually improved it a little, with the
revelation that @property can take multiple values. My apologies for
that wrong example, then, I'll try to fix that part ASAP. Trying to
think about which cases would then require wrappers in RDFa, the only
situation I've come up with is when the value should be reused for
properties about different subjects. And, to my surprise, just
realized that CRDF in embedded form didn't handle those case neither!
So, my most sincere thanks for highlighting this, since you have
revealed a serious issue on CRDF that will get fixed on the next
iteration of the document (hopefully due for late tuesday or early
wednesday).

 Part 0.3 of your document claims that RDFa is designed for XHTML
 exclusively. This is not the case - the designers of RDFa went out of
 their way to make its use feasible in *any* XML or XML-like language. SVG
 Tiny 1.2 includes the RDFa attributes, so RDFa can be used in SVG.
My apologies here for such a bad wording, although your reply confirms
the idea behind the wording: RDFa was part of the the future is XML
dream, thus not taking into propper account non-X HTML. Not to say
that it was the RDFa's fault, since that was a quite widespread belief
(I shared it myself for a long while). But RDFa's XMLish approach is
the root of many issues for tag-soup HTML; perfectly illustrated by
the ammount of controversy generated on these lists by the
xmlns:prefix syntax.
I'll make sure to change that wording to better describe the idea
behind it; and I'd like to thank you for highlighting the issue.

 Part 0.3 also states that both Microformats and RDFa require the
 human-readable values to be reused as the machine-
 readable ones.. Actually, RDFa provides @content and @resource which,
 respectively, over-ride human-readable text and human-intended link targets.
Again, my limited knowledge of RDFa has betrayed me. This, added to
Microformats missuse of abbr as a workaround, means that the issue
itself doesn't exist, at least not as initially percevied. I'm not
sure whether I'll remove that one entirely, or just briefly mention on
the Issues with Microformats section, due to the accessibility
issues with the abbr approach.

 Lastly, and most seriously, CRDF doesn't seem to distinguish between
 literals and resources.
This is definitely an important issue, which Tab already made me aware
of. Fortunately, it's easy to fix; and Tab himself provided a possible
solution, which is very likely to be part of the next version of the
document.

Until I add the fixes to the document, it's only left to reiterate my
thanks for your feedback.

Regards,
Eduard Pascual


Re: [whatwg] Annotating structured data that HTML has no semantics

2009-05-17 Thread Eduard Pascual
On Sat, May 16, 2009 at 10:02 AM, Leif Halvard Silli l...@malform.no wrote:
 [...]
 But may be, after all, it ain't so bad. It is good to have the opportunity.
 :-)
This is the exactly the point (at least, IMO): RDFa may be quite good
at embedding inline metadata, but can't deal at all with describing
the semantics that are inherent to the structure. OTOH, EASE does
quite the latter, but can't handle the former at all.
That's why I was advocating for a solution that allows either
approach, and even mixing both when appropriate.

On a side note, about the idea of mixing CSS+EASE or CSS+CRDF or
CSS+whatever: my PoV is that these *should* not be mixed; but any
CSS-like semantic description would benefit from some foolproofing,
ensuring that if an author puts CRDF this would get ignored by CSS
parsers (and viceversa). In addition, CSS's error-handling rules make
this kind of shielding relatively easy. OTOH, adding the semantic code
as part of the CSS styling, or trying to consider this as part (or
even as an extension) of the CSS language is wrong by definition:
semantics is not styling; and we should try to make authors aware
enough of the difference.

Regards,
Eduard Pascual