🚀 go-pugleaf

Thanks to all who've responded (both here and via E-mail).   Yes, it
occurred to me that evening (after posting) that I'd also need a
backtracking loop.  I checked the following morning, and, sure enough,
it *had* worked; I simply had too many facts to see that one was gone. 
BTW, I'm using the Edinburgh C-Prolog interpreter.
I have it running now.  FWIW, I have a *large number* of Object rules,
of which about 20% are obsolete.  It's taking about two hours of CPU
time on a 8820 to reduce.  Would the usage of SETOF/BAGOF be faster?

A couple of you mentioned the use of SETOF or BAGOF as an alternative
method of locating the redundant facts.  How can I put this: "That went
*way* over my head", or to summarize, "Huh??"  I'm still trying to
understand SETOF/BAGOF.  Perhaps I've had too many years of structured
(3rd generation) programming, or maybe it's just that I can be *dense*!   8^)
One proffered example (that I *almost* understand) was from Bart Demoen:
	reduce_objects :- bagof(object(I,X,Y), J^(object(I,X,Y), object(J,X,Y),
I<J), L),
			delete_objects_in_list(L).
	delete_objects_in_list([]).
	delete_objects_in_list([Obj|T]) :- retract(Obj), delete_objects_in_list(T).
I *do* understand what "delete_objects_in_list" is doing.   8^)
Would some *kind* soul translate/comment *profusely* the BAGOF call?

Thanks in advance,
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Sheldon E. Smith			!Email:
Digital Equipment Corporation		! ssmith%ncdel.enet.dec@decwrl.dec.com
Minneapolis, Minnesota			! ...!decwrl!ncdel.enet.dec.com!ssmith
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