ch03ex02.pro

prolog,人工智能推理程序,运行环境prolog

/*
   Turbo Prolog 2.0 Chapter 3, Example Program 2
   
   Copyright (c) 1986, 88 by Borland International, Inc
   
*/
   
predicates
   can_buy(symbol, symbol)
   person(symbol)
   car(symbol)
   likes(symbol, symbol)
   for_sale(symbol)

clauses
   can_buy(X, Y) :-
	person(X),
	car(Y),
	likes(X, Y),
   	for_sale(Y).
   
   person(kelly).
   person(judy).

   car(lemon).
   car(hot_rod).

   likes(kelly, hot_rod).
   likes(judy, pizza).

   for_sale(pizza).
   for_sale(lemon).
   for_sale(hot_rod).