[rdfweb-dev] Time's running out?

Danny Ayers danny666 at virgilio.it
Fri Aug 8 11:44:15 UTC 2003

> The stats show a large number of infrequently used tags, many of which
> are not in the spec. They also show a large number of incorrectly used
> tags that are in the spec. All these represent write-only data.

Tags is a probably a misnomer here, if the RDF is valid then what we're
talking about are classes.

> response to this is to ignore it.

It depends - if we had

 foaf:name "Jack"
 foaf:shoeSize "43"

and your app doesn't know anything specific about foaf:shoeSize, it can
still use the information. For example, it might just display the property
name and value (I think Morten's FOAF Explorer might do this). A potentially
more significant use is being able to respond to queries on the data -
another app asks "what do we know about Jack?" and this app returns the

Another response to this is to make
> efforts to encourage validation against an agreed spec. I've suggested
> this in the past but have been told that "Validating FOAF" does not mean
> anything except in the sense of validating against RDF. And that
> validating against the spec is back to front because the spec is a
> reflection of current practice not an arbiter. So Libby's (sorry to take
> this as an example, Libby) FOAF file is just as valid as mine despite
> the fact that Libby's is so far from what I can code to expect that it's
> essentially unusable to me[1].

Again, this depends on what you want to do with the data. I would think it
likely that most FOAF apps with support the key classes and properties such
as foaf:Person and foaf:knows. Once parsed, the structure described is the
same whatever the source looks like. I've just had a look at the graph
(using the W3C validator) of Libby's file at


and this core stuff looks as it should.

> Indeed. I don't want to experiment with RDF tools chewing on data. I
> don't want to raise awareness of the expressive power of multiple
> namespace documents. I don't want to enable semantic homepages. To be
> crude and somewhat tactless, I don't want to live in an ivory tower.
> I want to write apps.

Great! So in that context, what are the specific problems you're having? In
what respect is Libby's data unusable?


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