examples/zebra.lisp @ 8cd3257c58e3

Name the subterm-handling instructions something not completely stupid

The `unify-*` instructions in the original WAM are used both in both program
mode and query mode.  In program mode, they are used to unify subterms of
arguments with things.  In query mode, they are used to write the subterms of
the arguments into the head.

You may have noticed the common word in both of these descriptions is "subterm"
and not "unify".  Let's use that word to name the instructions so it's less
confusing.
author Steve Losh <steve@stevelosh.com>
date Sun, 10 Jul 2016 14:28:48 +0000
parents ae2b13a9a629
children (none)
(in-package #:bones.paip)

(clear-db)

(rule (member ?item (?item . ?)))
(rule (member ?item (? . ?rest))
      (member ?item ?rest))

(rule (next-to ?x ?y ?list)
      (in-order ?x ?y ?list))

(rule (next-to ?x ?y ?list)
      (in-order ?y ?x ?list))

(rule (in-order ?x ?y (?x ?y . ?)))
(rule (in-order ?x ?y (? . ?rest))
      (in-order ?x ?y ?rest))

(rule (= ?x ?x))

(rule
 (zebra ?houses ?water-drinker ?zebra-owner)
 ;; Houses are of the form:
 ;; (HOUSE ?country ?pet ?cigarette ?drink ?color)

 (= ?houses
    ((house norway ? ? ? ?)
     ?
     (house ? ? ? milk ?)
     ?
     ?))

 (member   (house england ?      ?            ?            red   ) ?houses)
 (member   (house spain   dog    ?            ?            ?     ) ?houses)
 (member   (house ?       ?      ?            coffee       green ) ?houses)
 (member   (house ukraine ?      ?            tea          ?     ) ?houses)
 (member   (house ?       snails winston      ?            ?     ) ?houses)
 (member   (house ?       ?      kools        ?            yellow) ?houses)
 (member   (house ?       ?      lucky-strike orange-juice ?     ) ?houses)
 (member   (house japan   ?      parliaments  ?            ?     ) ?houses)
 (in-order (house ?       ?      ?            ?            ivory )
           (house ?       ?      ?            ?            green ) ?houses)
 (next-to  (house ?       ?      chesterfield ?            ?     )
           (house ?       fox    ?            ?            ?     ) ?houses)
 (next-to  (house ?       ?      kools        ?            ?     )
           (house ?       horse  ?            ?            ?     ) ?houses)
 (next-to  (house norway  ?      ?            ?            ?     )
           (house ?       ?      ?            ?            blue  ) ?houses)

 (member (house ?water-drinker ? ? water ?) ?houses)
 (member (house ?zebra-owner zebra ? ? ?) ?houses))

(time (query-all (zebra ?houses ?water ?zebra)))
; (declaim (optimize (speed 3) (safety 0)))