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Re: BLD: two issues with the BNF

From: Jos de Bruijn <debruijn@inf.unibz.it>
Date: Fri, 11 Jul 2008 18:37:41 +0200
Message-ID: <48778C55.3040102@inf.unibz.it>
To: kifer@cs.sunysb.edu
CC: RIF <public-rif-wg@w3.org>



Michael Kifer wrote:
> On Fri, 11 Jul 2008 09:29:54 +0200
> Jos de Bruijn <debruijn@inf.unibz.it> wrote:
> 
>>>> 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.
>>> There was a mistake in the math syntax. Groups should also allow atomic
>>> formulas. Fixed.
>> One more thing: atomic formulas can also contain variables.  I guess 
>> that such non-ground atomic formulas should not be allowed in groups?
> 
> I see no reasons why such formulas should be disallowed. They are allowed as part of the KB, so why disallow them in groups?


I thought all variables in BLD need to be explicitly quantified?

-- 
Jos de Bruijn            debruijn@inf.unibz.it
+390471016224         http://www.debruijn.net/
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Received on Friday, 11 July 2008 16:38:10 GMT

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