Subject: "Common feature sets"

From: Graham Klyne <[email-masked]>
Date: Thu, 21 Jan 1999 12:34:57 +0000

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-masked])

---

From: Ted Hardie <[email-masked]>
Date: Thu, 21 Jan 1999 16:13:01 -0800 (PST)

Graham writes:
> Quoting Ted:

If three represenations each require 5 features, three of which are constant
and the other two of which interdepend, how do we represent the three.  So
imagine the features are:

(feeble, greeble, beeble, habid, rabid)
(feeble, greeble, beeble, humid, rumid)
(feeble, greeble, beeble, zord, dord)

Can we make it something like:

2634062802=(feeble, greeble, beeble)
(2634062802, habid, rabid)
(2634062802, humid, rumid)
(2634062802, zord, dord)

Obviously, using 2634062802 rather than "feeble, greeble, beeble" isn't a
big win, but a cksum will be more effective when we have things like

u.http://www.microsoft.com/win-nt/features/svideo
u.http://www.netscape.com/communicator/features/open-gl-texturing
u.https://www.datefellows.com/watermarks/version4

as features.

I hope that is at least moderately clearer.
				best,
					Ted Hardie