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Re: Practical N3/SW Uses

From: Sean B. Palmer <sean@mysterylights.com>
Date: Sun, 28 Jan 2001 19:49:37 -0000
Message-ID: <01c001c08963$730be1a0$576b073e@z5n9x1>
To: <jos.deroo.jd@belgium.agfa.com>
Cc: <swag-dev@yahoogroups.com>, <www-rdf-interest@w3.org>
> Thanks a lot for the "coined" example!

Thanks for playing around with it! I've added some more examples to
http://purl.org/swag/cwm if you (and hopefully some others as well) are
interested. Now we can filter N3 stuff out on the Web, thanks to Aaron
installing CWM...

> we get the results found at http://www.agfa.com/w3c/tmp/coinedByp.n3
> There are 16 deduced rules:coined statements (I hope this is correct ...)

Yes, this is correct. This is more or less what CWM outputs, but instead of
printing out the whole the whole implication (x implies y), it just gives
"y", which is more useful in this case, but may not be in others.
hmmmm.....maybe you could run "x implies (y implies z)" on CWM, but I bet
it'll fall on it.

> 1. An identifier id without colon is treated as <#id>.

Is it? It shouldn't be according to the syntax: it should treat it as an
undetermined keyword, I think.

> 2. @prefix is better and bind is treated as deprecated.

Yes. "bind" automatically adds a "#" to the end of the URI, whereas
"@prefix" does not.

> 3. Is it <http://www.w3.org/2000/10/swap/log.n3> or
>    <http://www.w3.org/2000/10/swap/logic.n3>?

log.n3 is the namespace, logic.n3 is the Schema. This may have been a TimBL
oversight.

> 5. An implementation of = predicate and [] contents.

     = daml:equivalentTo daml:equivalentTo .
     [] = rdf:Description .

I think. Note that that isn't valid N3! Just mock N3 to explain what I
think the syntax is. Maybe lookin at the BNF is the best idea:
http://www.w3.org/DesignIssues/Notation3
I think that the CWM has a lot of "SW Cheerleading" potential, i.e. the
ability to get useful data out of other useful data, and the ability to
re-use filters. I have made one really useful generic filter, that works
out equivalence:-

@prefix log: <http://www.w3.org/2000/10/swap/log.n3#> .
@prefix daml:  <http://www.daml.org/2000/10/daml-ont#> .
<>   log:forAll <#x> , <#y> , <#p> , <#q> .
{ <#q> daml:equivalentTo <#p> . <#x> <#p> <#y> . }
   log:implies
{ <#x> <#q> <#y> .} .

- http://infomesh.net/swag/n3/hackings/bmwdeeleyf.n3

But I'd appreciate more thoughts, ideas, and stuff to parse. It's hard
thinking up useful and quick examples.

--
Kindest Regards,
Sean B. Palmer
@prefix : <http://webns.net/roughterms/> .
[ :name "Sean B. Palmer" ] :hasHomepage <http://infomesh.net/sbp/> .
Received on Sunday, 28 January 2001 14:54:01 GMT

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