Re: Issue: EQUAL-STRUCTURE (Version 4)

[Jeff Dalton <jeff%aiai.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK>]

> Can we not say "CLOS instances" and just use "instances"?  The single
> word is not ambiguous now that CLOS is adopted.  I don't want users of a
> Flavors compatibility package to get worried that "CLOS instances" and
> "Flavors instances" might be different.

I'm inclined to agree that "instances" is better, but Kent's reason
makes me wonder.  Suppose someone implements an object system where
is isn't possible to descend instances (perhaps they're closures).
I don't think we can say they can't be called "instances".  What it
would come down to would be that they weren't implemented as CLOS
instances and so the clause in EQUALP didn't apply.

So we want to say "instances", we have to say somewhere what "instance"
means in Common Lisp, and then it will be those instances we'll be talking
about in EQUALP.

It would then be up to the documentation for Flavors compatibility
packages and the like to how their concept of instances maps onto
Common Lisp.  And I think that is how it should be.

So I agree with the first reason (it's no longer ambiguous), but
not the second.