[m-rev.] For review: inst any non-locals in promise_equivalent_solutions

[Ralph Becket]

Ian MacLarty, Monday,  5 February 2007:
> On Mon, Feb 05, 2007 at 01:35:05PM +1100, Ralph Becket wrote:
> > Estimated hours taken: 1
> > Branches: main
> > 
> > Fix a bug where promise_equivalent_solutions complained both if you did or did
> > not include non-locals with inst any in the var list.  Such vars *must* now be 
> > included in the list.
> 
> In the reference manual is says:
> 
> This goal promises that @var{Vars} is the set of variables bound by
> @var{Goal}, and that while @var{Goal} may have more than one solution,
> all of these solutions are equivalent with respect to the equality
> theories of the variables in @var{Vars}.
> 
> Is this still valid if some of the vars have inst any?  An inst any
> variable may represent many (different) solutions.  My understanding is
> that you just want a determinism cast, you don't want to promise that
> the solutions are all equivalent.

It's quite consistent to say that if the goal constrains X in some way,
then all ways in which it might do it are indistinguishable.
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