Re: [whatwg] Link rot is not dangerous

On May 15, 2009, at 3:50 PM, Tab Atkins Jr. wrote:

> On Fri, May 15, 2009 at 1:32 PM, Manu Sporny <msporny@digitalbazaar.com 
> > wrote:
>> Tab Atkins Jr. wrote:
>>> Reversed domains aren't *meant* to link to anything.  They shouldn't
>>> be parsed at all.  They're a uniquifier so that multiple  
>>> vocabularies
>>> can use the same terms without clashing or ambiguity.  The Microdata
>>> proposal also allows normal urls, but they are similarly nothing  
>>> more
>>> than a uniquifier.
>>>
>>> CURIEs, at least theoretically, *rely* on the prefix lookup.  After
>>> all, how else can you tell that a given relation is really the same
>>> as, say, foaf:name?  If the domain isn't available, the data will be
>>> parsed incorrectly.  That's why link rot is an issue.
>>
>> Where in the CURIE spec does it state or imply that if a domain isn't
>> available, that the resulting parsed data will be invalid?
>
> Assume a page that uses both foaf and another vocab that subclasses
> many foaf properties.  Given working lookups for both, the rdf parser
> can determine that two entries with different properties are really
> 'the same', and hopefully act on that knowledge.
>
> If the second vocab 404s, that information is lost.  The parser will
> then treat any use of that second vocab completely separately from the
> foaf, losing valuable semantic information.
>
> (Please correct any misunderstandings I may be operating under; I'm
> not sure how competent parsers currently are, and thus how much they'd
> actually use a working subclassed relation.)


RDFa parsers simply adhere to the parsing algorithm outlined in the  
RDFa specification. Their job is to extract the metadata found in the  
page and that's pretty much it. You are combining features from the  
broader RDF world with RDFa. The fact that we can lean on RDFS and OWL  
to more accurately describe that metadata should be considered an  
added bonus. However, I personally would like to see this as baby  
steps. We defined a general syntax for declaring metadata and  
describing resources in XHTML (soon hopefully HTML(x)), the current  
steps are people adding metadata to their sites and people learning  
how to make sense of that data. Google is defining a vocabulary they  
understand, Yahoo is both creating new and re-using existing  
vocabularies they understand. Anyone, can correct me if I'm wrong, but  
I thought the more advanced function where machines will apply  
inference to understand newly encountered vocabularies should be left  
as an exercise for others outside the RDFa group/work.

-Elias

Received on Friday, 15 May 2009 20:08:24 UTC