[m-dev.] Tabling [1/3]

[Oliver Hutchison]

On Thu, 12 Mar 1998, Fergus Henderson wrote:

> 
> > > If there is some other useful semantics, e.g. minimal
> > > model or well-founded model semantics,
> > > then there should be different pragmas to ask for them.
> > > For example, that's what `pragma minimal_model' is for.
> > > 
> > > If I recall correctly (a big if! ;-), SLG resolution implements
> > > the well-founded model semantics, which (again if I recall correctly)
> > > is an extension of minimal model semantics to programs with negation.
> > > I thought we decided to use `pragma minimal_model' simply because
> > > that was a slightly less frightening term than `pragma well_founded_model'.
> > 
> > Yes. But SLG-d is a subset of SLG supporting only definite programs.
> 
> Oh, I see.  So what you've implemented is exactly the minimal_model
> semantics.  That is probably why we called it `pragma minimal_model' ;-)
> 
> Can you remind me what the difficulty in implementing full SLG
> resolution is?  i.e. what would be required to implement
> `pragma well_founded_model'?
> 

I suspect if I tried to expain it we would both get confused again :-) If
you have a look at pages 80-82 in ~ohutch/thesis.ps you will understand
or you will see how easy it is and tell me!