RE: Comments on the new RDF Test Cases draft

On Thu, 30 May 2002, Brian McBride wrote:

> At 12:43 29/05/2002 -0400, Massimo Marchiori wrote:
>
> > > When I said no, I was thinking of parser tests, which in practise is what
> > > people will be using the tests for.  I think I was wrong as the question
> > > Massimo asked was not well formed.
> > >
> > > We are not defining any notion of compliance, so there is no
> > > answer.  We do
> > > say, that for a given test case, the input RDF/XML represents the same
> > > graph as the supplied n-triples.  That is syntactic equivalence and that
> > > seems right to me.  Notions of semantic equivalence can be kept separate.
> > >
> > > Sorry, Massimo; I was in too much of a hurry answering your mail
> > > and failed to engage brain above first gear.
> >
> >Ok, that's a reasonable way out: don't give any conformance status to the
> >Test Cases.
> >In this case, my suggestion is to smoothen the current language (which now can
> >lead to think there's some normative conformance definition creeping in,
> >i.e., defining normatively conformance of an "RDF parser").
> >In particular, whereas now there are wordings like
> >+ for positive tests:
> ><quote>
> >A parser is considered to pass the test if it produces a graph isomorphic
> >with the graph described by the N-triples output document.
> ></quote>
> >+ for negative tests:
> ><quote>
> >A parser is considered to pass the test if it correctly holds the input
> >document to be in error.
> ></quote>
>
> That's a good point.  Jan - what do you think?

I can make it as wooly as you like.

> >more milder words can be used, for example using something like
> >"the expected output of an RDF parser is a graph ... bla"
> >which conveys the intuition that, reasonably, a parser should do what
> >stated here,
> >but doesn't normatively try to impose some notion of "test passing" for parser
> >(which leads to conformance, which leads to the syntactic/semantic issue,
> >and/or
> >to a definition of what an RDF parser is....).
> >For the negative tests, similar thing, like e.g., "the expected behaviour
> >of an RDF
> >parser is to raise an error".
> >
> >Note the entailment part, on the other hand, does a good job to avoid the
> >"conformance problem", as it writes rather neutrally:
> ><quote>
> >the test succeeds if the entailment holds
> ></quote>
> >(i.e., the "test" is made the subject of the sentence).
> >
> >Therefore, such "word smoothering", plus a precise definition of isomorphism,
> >suffice. But, note that if we go along the "smoothering way", the same
> >problem of
> >a precise definition of isomorphism can be nicely dropped as well, as the
> >wording can
> >well say that the "expected output" is the given N-triple one, and just be
> >silent on the isomorphism issues at all (as, it's rather clear that N-triple
> >output is defined modulo renaming of blank nodes, and in any case,
> >crucially, no
> >*formal* definition is then needed as the Test Cases contain clarification
> >guidelines,
> >and not formal normative definition of "test passing for parsers").
> >
> >-M

The reason for the wording is that the author of a popular parser (that
is, Dave Beckett) said that he wanted some explicit words in the
document to tell him exactly what he (as a parser writer) was supposed
to do to see if his parser agreed with the expected output from the test
cases. If you want to call that "conformance", fine, I suppose it fits
that definition.

jan

PS. Sorry to not have followed this conversation more closely - my
subscription to www-rdf-comments appears to be playing up.



-- 
jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/
Tel +44(0)117 9287088 Fax +44 (0)117 9287112 RFC822 jan.grant@bris.ac.uk
Whenever I see a dog salivate I get an insatiable urge to ring a bell.

Received on Friday, 31 May 2002 05:20:31 UTC