Re: RDFa in HTML5

Hi, Niklas!

2012/1/4 Niklas Lindström <lindstream@gmail.com>:
> Hello Augusto!
>
> On Wed, Jan 4, 2012 at 11:08 AM, Augusto Herrmann
> <augusto.herrmann@gmail.com> wrote:
>> The examples are displayed as (escaped) html code in the rightside
>> panel on the following page: http://vocab.e.gov.br/2011/03/vcge
>>
>> People are meant to copy/paste the code, or just read and undestand,
>> in order to learn how to mark up their own pages stating that it's
>> about a subject in this controlled vocabulary. That's why we left the
>> reference to the page as an empty relative URL (which should resolve
>> to whatever address the page is loaded into).
>>
>> But we also did eat our own dog food: that page also states it's about
>> the VCGE controlled vocabulary, by using RDFa 1.1 and Microdata like
>> this (lines 21-25):
>>
>> <!-- Marking up subject using RDFa: the page is about VCGE -->
>>  <meta property="http://purl.org/dc/terms/subject"
>> content="http://vocab.e.gov.br/2011/03/vcge#esquema" />
>
> Using meta with @content like this produces a literal, so from the
> above you'll get:
>
>    <http://vocab.e.gov.br/2011/03/vcge.html> dc:subject
> "http://vocab.e.gov.br/2011/03/vcge#esquema"@pt_br .
>
> , i.e. a literal (notice that it's also tagged with the language
> "pt_br", inherited from @lang in the html element).
>
> Verify this with e.g. the RDFa 1.1 distiller at [1].
>
>
>> <!-- Marking up subject using Microdata: the page is about VCGE -->
>>  <meta itemscope itemprop="http://schema.org/about"
>> content="http://vocab.e.gov.br/2011/03/vcge#esquema" />
>>
>> The triple that should be extracted from the RDFa is:
>>
>> <http://vocab.e.gov.br/2011/03/vcge> dcterms:subject
>> <http://vocab.e.gov.br/2011/03/vcge#esquema> .
>
> To get this triple, you should use:
>
>    <link rel="http://purl.org/dc/terms/subject"
> href="http://vocab.e.gov.br/2011/03/vcge#esquema" />
>
> (or @property instead of @rel, since RDFa 1.1 allows them to work the
> same when used in conjunction with @href or @resource).
>
> Think of the literal resulting from the meta element as a "value
> primitive", and the link as a proper *reference* to a resource which
> can be the subject of more triples. (There's more theory to it than
> that, but I hope it explains some of it.)
>
> Best regards,
> Niklas
>
> [1]: http://www.w3.org/2007/08/pyRdfa/Shadow.html

Thanks for pointing it out to us! We've since corrected the page and
also the example code.

PS: We'll answer your other message soon.

Best regards,
Augusto Herrmann

Received on Friday, 6 January 2012 12:35:45 UTC