Re: Comments about microdata

On May 13, 2009, at 12:54, Henri Sivonen wrote:

> One of the most common points made in favor of RDFa in contrast to  
> microformats is the ability to say things about external resources.  
> Microdata in HTML5 has a predefined property called 'about'.  
> However, it is rather awkward as a mechanism for saying things about  
> external resources. I think it would be preferable to remove this  
> predefined property and instead make an a, area, audio, embed,  
> iframe, img, link, object, source, or video element imply its URI as  
> the subject URI when the element is used as an item.
>
> That is, this markup:
> <img alt='Hedral the cat' src='http://www.example.com/hedral.jpg'  
> id=hedral item> (Photo licensed under the <a href='http://creativecommons.org/licenses/by/3.0/' 
>  itemprop='license' subject=hedral>Creative Commons Attribution 3.0  
> Unported License</a>.
> would generate the following triple:
> <http://www.example.com/hedral.jpg> <http://www.w3.org/1999/xhtml/vocab#license 
> > <http://creativecommons.org/licenses/by/3.0/> .
>
> In JSON, there could be a string entry with the key 'url' next to  
> 'type' and 'properties'.
>
> - -
>
> Considering the example above, it might be useful to consider an  
> optimization allowing itemprops inside the legend of a figure to  
> apply to the first embedded-content child of the same figure. (Yeah,  
> this might be bad feature creep.)


Having realized that you can do this with fewer idrefs and special  
rules already, I withdraw the above comments.

For reference, you can do:
<figure item>
<img alt='Hedral the cat' src='http://www.example.com/hedral.jpg'  
itemprop='about'>
<legend>Photo licensed under the <a href='http://creativecommons.org/licenses/by/3.0/' 
  itemprop='license'>Creative Commons Attribution 3.0 Unported  
License</a></legend>
</figure>

-- 
Henri Sivonen
hsivonen@iki.fi
http://hsivonen.iki.fi/

Received on Wednesday, 20 May 2009 06:57:42 UTC