W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > September 2002

Re: DECIDED: untidy semantics

From: Jan Grant <Jan.Grant@bristol.ac.uk>
Date: Sun, 22 Sep 2002 12:48:32 +0100 (BST)
To: Jos De_Roo <jos.deroo.jd@belgium.agfa.com>
cc: w3c-rdfcore-wg <w3c-rdfcore-wg@w3.org>
Message-ID: <Pine.GSO.4.44.0209221237090.20899-100000@mail.ilrt.bris.ac.uk>

On Sat, 21 Sep 2002, Jos De_Roo wrote:

> I'm recording outstanding dissent too !!!

On reflection, add me to the "can't live with" camp. Not because of
implementation difficulties - I was enamoured of P++ ages ago and since
I had an implementation that maps resources, bnodes and literals onto
internal IDs, adding the API extensions to deal with untidy literals
wasn't a problem.

However, while it's not overly onerous to implement in every case
(although it might be in many implementations), the resulting API was an
absolute fag to code to; small experiments quickly descended into
graph-grovelling.

Since one might assume that every producer of RDF is also a consumer,
but that there are consumers out there who are not producers, favouring
the modellers over the implementers also seems to be tail-wagging-dog
stuff. Those who have to utilise RDF APIs should also be considered. I'm
not sure how to explain/sell this to people.

Incidentally, the test cases are going to be somewhat delayed since we
no longer have any way of comparing ntriples-expressed graphs for
equality, so parser tests are (for the moment, at least) impossible to
automate.

Patrick's email arguments were very persuasive; in fact, at the telecon,
I overlooked what my primary objections (outlined above) were. However
elegant this "solution" might be, I'm unconvinced of its necessity. That
is, the first question isn't "can we implement this" but "should we?".

jan

PS. On the untidyness of literals: I'm still not certain why untidy
literals are tagged with what PS calls "system IDs" as opposed to
bnodes, the space of which may intersect with non-literal-labelling
bnodes. If we're after elegance and completeness, then it seems
reasonable to want to express

	_:a rdf:subClassOf eg:someDataType .
	_:b eg:foo (_:a, "blarg") .

although this falls into the trap of talking about untyped literals in
the abstract (ie, in terms of "blarg"s) rather than grounded in concrete
examples.

-- 
jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/
Tel +44(0)117 9287088 Fax +44 (0)117 9287112 http://ioctl.org/jan/
Donate a signature: http://ioctl.org/jan/sig-submit
Received on Sunday, 22 September 2002 07:51:28 EDT

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:51:01 EDT