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Re: Pragmatism: An EARL Processing Example (that actually works)

From: Sean B. Palmer <sean@mysterylights.com>
Date: Sun, 18 Feb 2001 14:38:07 -0000
Message-ID: <002501c099b8$6be0ca20$530b073e@z5n9x1>
To: <w3c-wai-er-ig@w3.org>, "Leonard R. Kasday" <kasday@acm.org>
> I'm having trouble grokking :sean, :len, and :william as
> verbs or properties

What if I then wrote:-

     :sean rdfs:comment "Sean's assertion of how valid a page is" .

I was incorrectly getting you to work out what the URI "<#sean>" meant,
which is not good practise... but we all do it to save time. Note this from
he N3 Primer [1]:-

     The identifiers are just identifiers - the fact that the letters p a t
     are used doesn't tell anyone or any machine that we are talking
     about anyone whose name is "Pat" -- unless we say <#pat>
     <#name> "Pat". The same applies to the verbs - never take the
     actual letters c h i l d as telling you what it means - we will find
     out how to do that later.

Property names are just URIs, they don't have anyspecial meaning... for
exmaple <#fruit> could actually be a sort of car if I so wished it to be...
for for sanity purposes, in examples we try to come close to the actual
purpose of the prop. Think of :sean not as ":seanSays", but as

>    earl:hasEvaluation [earl:humanEvaluator :sean   ;
>    wcag:compliance wcag:A  ] ;

I think that says that I evaluated the page and that it has a rating of
wcag:A, rather than I evaluated the page and gave it that rating... But I
never quite understand that aspect of RDF... people tend to rant on about
the difference between "everybody loves someone" and "someone loves
someone"; that's what the log:forAll thing is in the logc namespace.

> :sean    earl:asserts {<http://testpage.org> wcag:compliance
> wcag:A } .

Yes, that is better... it says that I am asserting that this page has this
compliance. I think that:-

     "Evaluator" earl:asserts { "context" } .

Is now clearly a fundamental part of the EARL syntax. Note that according
to the EARL Overview [1], :sean could be defined as:-

     :sean a earl:Person .

Because in the vocabulary, an earl:Person is defined as:-

     earl:Person rdfs:comment "x a earl:Person" ;
     rdfs:subClassOf earl:Evaluator .

> I suppose we can do it any way we want, even with :sean :len
> and :william as verbs or properties, but like I say I find it hard
> to grok that.

Yes... I think as EARL is going to be a subset of RDF, and thus possibly
not have the total freedom of RDF, we should get these "practises" encoded
into a "syntax".

Kindest Regards,
Sean B. Palmer
@prefix : <http://webns.net/roughterms/> .
[ :name "Sean B. Palmer" ] :hasHomepage <http://infomesh.net/sbp/> .
Received on Sunday, 18 February 2001 09:38:23 UTC

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