Re: Tentative contribution to the "URI issue"

> Hassan Aït-Kaci wrote:
> > Michael Kifer wrote:
> 
> >> Second, in a complex KB, you always have internal predicates that 
> >> shouldn't
> >> be visible outside. Why should they be given a URI?
> > 
> > I agree even more! One detail of momentous importance that seems to escape
> > anyone envioning a system where *all* identifiers and constants are URIs
> > is that these are precisely that - *universal*. In other words, they
> > defeat the concepts of local scoping, hiding, and modularity - something
> > desirable for any respectable programming idiom. 
> 
> Agreed but as I said in a separate posting, scoping is orthogonal to 
> identifier spelling. For example, in Java my inner class has a fully 
> qualified classname whether or not it is public, protected or even 
> private scope.


The bottom line is that this issue is very controversial.
I can't see a good logic behind first given a universal name to an object
and then trying to hide it through scoping. It seems that Hassan has the
same opinion.


> > Namespaces are a poor-man
> > way of somehow working around this flatness.
> 
> Agreed. Has someone suggested that namespaces might be the sole basis 
> for a scoping mechanism for RIF? I doubt it. I assume we'll want notions 
> of, especially variable, scoping which are much richer than that (indeed 
> I don't expect variables to be named by URIs at all).

Variables are always scoped to rules. Giving them URI based names is a
misnomer and makes no sense.  I am glad that you also don't think this is
useful.


	--michael  

Received on Wednesday, 21 March 2007 15:46:31 UTC