;;; ****************************************************************
 ;;; OPS5 Interpreter ***********************************************
 ;;; ****************************************************************
 ;;; This Common Lisp version of OPS5 is in the public domain.  It is based
 ;;; in part on based on a Franz Lisp implementation done by Charles L. Forgy
 ;;; at Carnegie-Mellon University, which was placed in the public domain by
 ;;; the author in accordance with CMU policies.  Ported to Common Lisp by 
 ;;; George Wood and Jim Kowalski. CMU Common Lisp modifications by
 ;;; Dario Guise, Skef Wholey, Michael Parzen, and Dan Kuokka. 
 ;;; Modified to work in CLtL1, CLtL2 and X3J13 compatible lisps by 
 ;;; Mark Kantrowitz on 14-OCT-92.
 ;;; 
 ;;; This code is made available is, and without warranty of any kind by the
 ;;; authors or by Carnegie-Mellon University.
 ;;;
 
 (reset-ops)
 
 (literalize monkey
 	at
 	on
 	holds)
 
 (literalize object
 	name
 	at
 	weight
 	on)
 
 (literalize goal
 	status
 	type
 	object
 	to)
 
 (p mb1
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on ceiling)
     -->
 	(make goal ^status active ^type move ^object ladder ^to <p>))
 
 
 (p mb2
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on ceiling)
 	(object ^name ladder ^at <p>)
     -->
 	(make goal ^status active ^type on ^object ladder))
 
 
 (p mb3
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on ceiling)
 	(object ^name ladder ^at <p>)
 	(monkey ^on ladder)
     -->
 	(make goal ^status active ^type holds ^object nil))
 
 
 (p mb4
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on ceiling)
 	(object ^name ladder ^at <p>)
 	(monkey ^on ladder ^holds nil)
     -->
 	(write (crlf) "grab" <w>)
 	(modify 4 ^holds <w>)
 	(modify 1 ^status satified))
 
 
 
 (p mb5
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on floor)
     -->
 	(make goal ^status active ^type walk-to ^object <p>))
 
 
 (p mb6
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on floor)
 	(monkey ^at <p>)
     -->
 	(make goal ^status active ^type holds ^object nil))
 
 
 (p mb7
 	(goal ^status active ^type holds ^object <w>)
 	(object ^name <w> ^at <p> ^on floor)
 	(monkey ^at <p> ^holds nil)
     -->
 	(write (crlf) "grab" <w>)
 	(modify 3 ^holds <w>)
 	(modify 1 ^status satisfied))
 
 (p mb8
 	(goal ^status active ^type move ^object <o> ^to <p>)
 	(object ^name <o> ^weight light ^at <> <p>)
     -->
 	(make goal ^status active ^type holds ^object <o>))
 
 
 (p mb9
 	(goal ^status active ^type move ^object <o> ^to <p>)
 	(object ^name <o> ^weight light ^at <> <p>)
 	(monkey ^holds <o>)
     -->
 	(make goal ^status active ^type walk-to ^object <p>))
 
 
 (p mb10
 	(goal ^status active ^type move ^object <o> ^to <p>)
 	(object ^name <o> ^weight light ^at <p>)
     -->
 	(modify 1 ^status satisfied))
 
 
 (p mb11
 	(goal ^status active ^type walk-to ^object <p>)
     -->
 	(make goal ^status active ^type on ^object floor))
 
 (p mb12
 	(goal ^status active ^type walk-to ^object <p>)
 	(monkey ^on floor ^at {<c> <> <p>} ^holds nil)
     -->
 	(write (crlf) "walk to" <p>)
 	(modify 2 ^at <p>)
 	(modify 1 ^status satisfied))
 
 
 (p mb13
 	(goal ^status active ^type walk-to ^object <p>)
 	(monkey ^on floor ^at {<c> <> <p>} ^holds <w> <> nil)
 	(object ^name <w>)
     -->
 	(write (crlf) "walk to" <p>)
 	(modify 2 ^at <p>)
 	(modify 3 ^at <p>)
 	(modify 1 ^status satisfied))
 
 (p mb14
 	(goal ^status active ^type on ^object floor)
 	(monkey ^on {<x> <> floor})
     -->
 	(write (crlf) "jump onto the floor")
 	(modify 2 ^on floor)
 	(modify 1 ^status satisfied))
 
 (p mb15
 	(goal ^status active ^type on ^object <o>)
 	(object ^name <o> ^at <p>)
     -->
 	(make goal ^status active ^type walk-to ^object <p>))
 
 
 
 (p mb16
 	(goal ^status active ^type on ^object <o>)
 	(object ^name <o> ^at <p>)
 	(monkey ^at <p>)
     -->
 	(make goal ^status active ^type holds ^object nil))
 
 
 (p mb17
 	(goal ^status active ^type on ^object <o>)
 	(object ^name <o> ^at <p>)
 	(monkey ^at <p> ^holds nil)
     -->
 	(write (crlf) "climb onto" <o>)
 	(modify 3 ^on <o>)
 	(modify 1 ^status satisfied))
 
 (p mb18
 	(goal ^status active ^type holds ^object nil)
 	(monkey ^holds {<x> <> nil})
     -->
 	(write (crlf) "drop" <x>)
 	(modify 2 ^holds nil)
 	(modify 1 ^status satisfied))
 
 (p mb19
 	(goal ^status active)
     -->
 	(modify 1 ^status not-processed))
 
 (p t1
 	(start 1)
     -->
 	(make monkey ^at 5-7 ^on couch)
 	(make object ^name couch ^at 5-7 ^weight heavy)
 	(make object ^name bananas ^on ceiling ^at 2-2)
 	(make object ^name ladder ^on floor ^at 9-5 ^weight light)
 	(make goal ^status active ^type holds ^object bananas))