Re: BLD: two issues with the BNF

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?

Received on Friday, 11 July 2008 16:36:53 UTC