"Common feature sets"

At 11:40 20/01/99 -0800, Ted Hardie wrote:
>Fair enough; I meant the scenario to express something about the
>problem which I didn't see addressed by other statements.  Looking
>back, that doesn't do a good job of describing the problem.

I believe this is all helping to find a common understanding...;

>Let me ask first whether you agree that the constant aspect might be
>applied to a grouping below the set.  

Er... I'm not sure I understand the question.

I have been thinking that the term "constant" is probably unhelpful, but
thus far have failed to find a better alternative.  I think the term
"common" might be closer (as in "common factor" or "common base values").
This, in turn, I think relates to Bill's "indirect reference".

The bit I really don't understand is "below the set".  This seems to
suggest one of two things (a) to subsets of some set of interest (which
set?), or (b) to the primitive elements from which the set is constructed
(feature collections?  feature tags and values?).

If (a) then my answer to your question is probably "yes".

If (b) then probably "no".

That is, I think indirect references should be dereferenced to yield either:
(i) a feature set expression
(ii) a collection of auxiliary feature predicates

I personally prefer (ii) because it tends to move the inderect reference
syntax away from the main feature expression.  But I also see that a final
proposal might permit either.

#g

------------
Graham Klyne
([email protected])