Re: ASN issue: leaf class == visible class?

> >>    class NAF
> >>
> >>       subclass StratifiedNaf
> >>
> >>	   subclass WellFoundedNaf
> >>
> >>	   subclass StableModelNaf
> 
> Hmmm, you mean to say that I need to specify which naf I use ALWAYS?
> In this case we rather call the first class
>      PerfectModelNaf
> since this is what it is on the pure semantic basis. The perfect model 
> semantics is simply only defined for stratified programs. Systems which 
> implement it -- and it seems that there are no systems which only allow 
> strat naf and do check is -- norlmally deploy perfect model semantics 
> and just fault in case the program is unstratified.

Ah, that makes sense.   One might also call it "StratifiedOnlyNaf",
maybe...

> To call it stratnaf sounds like stratnaf would be something *different* 
> from well-founded or stable negation, which it is not in case the 
> program is stratified. Why I wanted to have the subclassing in first 
> place was because my understanding was that I wanted to express that in 
> the stratified case both well-founded and stable coincide.

I don't think the class hierarchy gives you that in any formal way.  Can
you say what you were thinking/hoping the class hierarchy would provide
here?   Did you want RIF documents to sometimes be written not saying
which kind of NAF was intended?

    -- Sandro

Received on Friday, 13 July 2007 13:20:43 UTC