Clips编程——比较全局变量的值

Question

我正在学习 Clips 编程，但遇到了一个问题。我正在尝试使用 if-then-else 语句并测试两个全局变量是否相等。到目前为止，我有以下代码：

(defglobal ?*count_x* = 0)
(defglobal ?*count_y* = 0)
(defrule if_then_else
    ?x <- (?*count_x*)
    ?y <- (?*count_y*)
   =>
   (if  (eq ?x ?y)
      then
      (printout t "Yes, they are equal. " crlf)
      else
      (printout t "No, they are not equal." crlf)
      (printout t "x: " ?*count_x* crlf)
      (printout t "y: " ?*count_y* crlf))
      (retract ?x)
      (retract ?y)
)

这不是所有代码，计数器增加得很好，但这是不能正常工作的部分。有没有办法在不用 defrules 替换全局变量的情况下做到这一点？任何帮助将不胜感激，谢谢。

Answer 1

您不需要在规则的条件中绑定全局变量。直接引用它们：

(defglobal ?*count_x* = 0)
(defglobal ?*count_y* = 0)
(defrule if_then_else
   =>
   (if  (eq ?*count_x* ?*count_y*)
      then
      (printout t "Yes, they are equal. " crlf)
      else
      (printout t "No, they are not equal." crlf)
      (printout t "x: " ?*count_x* crlf)
      (printout t "y: " ?*count_y* crlf))
)