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Re: BLD: two issues with the BNF

From: Axel Polleres <axel.polleres@deri.org>
Date: Thu, 10 Jul 2008 17:32:32 +0100
Message-ID: <487639A0.5080201@deri.org>
To: Jos de Bruijn <debruijn@inf.unibz.it>
CC: RIF <public-rif-wg@w3.org>

Jos de Bruijn wrote:
> I uncovered two issues with the BNF in BLD.  For me they are not 
> critical for last call, but for some they might be.
> 
> The first issue is an error: Profile is not a Unicode string in the 
> presentation syntax, but it is a term (see section 2.4).

I do find this critical.

> The second issue is not an error, but it can be considered misleading 
> (the BNF is too liberal): in the presentation syntax, rules are 
> quantified rule implications.  So, an atomic formula is not a rule and 
> may thus not be directly included in a group.  According to the BNF, an 
> atomic formula can be considered a rule; this is misleading.

should be fixed. I think what you say can be easily addressed by
adding a comment to the EBNF inSection 2.6 which says the following:

"Note that in this grammar, we allow CLAUSES for rules and ATOMIC 
formulas as clauses as a shortcut for facts:
<ul>
<li>A CLAUSE rule <i>C</i> is in fact a shortcut for
<p>Forall <i>vars<sub>C</sub></i> ( <i>C</i> )</p>
and
</li>
<li>An ATOMIC Clause <i>A</i> is in fact a shortcut
<p> <i>A</i> :- "a" = "a" </p>
</li>
</ul>
"

We can also write:
   <i>A</i> :- And()

for the latter, BTW.


I would strongly opt for adding this clarification!

Axel

> Best, Jos


-- 
Dr. Axel Polleres, Digital Enterprise Research Institute (DERI)
email: axel.polleres@deri.org  url: http://www.polleres.net/

Everything is possible:
rdfs:subClassOf rdfs:subPropertyOf rdfs:Resource.
rdfs:subClassOf rdfs:subPropertyOf rdfs:subPropertyOf.
rdf:type rdfs:subPropertyOf rdfs:subClassOf.
rdfs:subClassOf rdf:type owl:SymmetricProperty.
Received on Thursday, 10 July 2008 16:33:13 GMT

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