Comment on RDFa 1.1 Core: Nested RDFa markup

Hello RDFa WG members,

This is a comment on Profiles in the latest RDFa WD [1]. It concerns  
the processing of RDFa markup that is nested inside an element that  
carries @property.

My understanding is that the latest draft prescribes the following  
behaviour: Nested RDFa markup inside the element is ignored and will  
not produce any triples if the element carries  
@datatype="rdf:XMLLiteral". Otherwise, any nested RDFa markup is  
processed as usual.

This behaviour causes a problem in the following situation. On web  
pages that contain blog posts or other “prose content”, it is often  
tempting to mark up the content with @property="ex:content" or  
something similar, so that the actual text content is accessible to  
processors. (Cf. SIOC, AtomOWL and hAtom.)

For the content to be useful, it has to be presented including HTML  
markup, so we can assume that @datatype="rdf:XMLLiteral" will and  
should be used in these situations.

This means however that any RDFa markup that may be present *inside*  
the content of the blog post or article will not be processed.

The effect is that implementers of content management systems,  
blogging software and similar tools who want to deploy RDFa have to  
make a choice between the following two options:

a) Make the entire content available to RDFa processors as an  
rdf:XMLLiteral, but authors using the software cannot add their own  
RDFa markup inside their posts.
b) Authors can use RDFa markup inside their posts, but the system does  
not make the entire content available to RDFa processors (or only as  
an unformatted string, which isn't very useful).

This is not a satisfactory choice. I believe that RDFa should provide  
a mechanism for capturing the content of an element as an  
rdf:XMLLiteral, while still processing markup inside that content so  
that it generates triples.

(Offhand I can't think of a reason why RDFa processing is suppressed  
at all inside XMLLiterals.)

Best,
Richard

[1] http://www.w3.org/TR/2010/WD-rdfa-core-20100803/

Received on Thursday, 5 August 2010 11:36:50 UTC