Re: Default value for @about depending on language [Re: Non-XHTML host languages for RDFa]

Hi Mark,

2009-12-01 11:31 Mark Birbeck <mark.birbeck@webbackplane.com>:
> But Christoph seems to be saying that his language needs to make lots
> of statements about the document itself, resulting in a common pattern
> of:
> 
>   <x id="y" about="#y">
>     ...
>   </x>
> 
> I don't have any immediate suggestions about how to work around this,
> although I'm sure we could come up with something. But I would caution
> against using @id in a language, to automatically generate a subject,
> since I think it will cause problems for that language in the longer
> term.

Indeed automatic generation of subjects may be tricky, and that's also why I
didn't pursue this any further.  The actual OMDoc situation is that certain
_elements_ denote formal concepts just by their existence.  E.g.
<definition><link rel="dc:creator" resource="x:me"/>...</definition> denotes a
definition that has some creator.  While it is strongly
recommended that such elements carry an @xml:id so that we can refer to them
by URI, it is not strictly required.  Now think of the above XML as "there
exists a definition created by x:me", and think of the correspondence of
bnodes to existentially quantified variables.  Compatibility to other RDFa
processors aside, if we had this automatic subject generation, the way of
doing it "right" would be:  If an @xml:id "i" exists, make #i the subject;
otherwise generate a bnode _:someid and make _:someid the subject.  Not sure
if that is nice, though, it is certainly a bit too far away from RDFa
compatibility.

Cheers,

Christoph

-- 
Christoph Lange, Jacobs Univ. Bremen, http://kwarc.info/clange, Skype duke4701