如何在 Clips 规则引擎中调试“检查 defrule 的适当语法”？

Question

(deftemplate illness
   (slot sickness)
   (multislot keywords))

(deffacts qestion-refrences
    (illness (sickness stunted-Groth)(keywords stunted groth))
    (illness (sickness pale-Yellow) (keywords pale yellow))
    (illness (sickness reddish-Brown)(keywords reddish brown))
    (illness (sickness stunted-Root)(keywords stunted root)))

(deffunction askquestion (?question)
    (printout t ?question)
    (bind ?answer (read))
    (if (lexemep ?answer) 
        then (bind ?answer (lowcase ?answer)))  
    ?answer)

(defrule determineSickness
    (bind ?f (askquestion "whot Does the plant seem to have ? "))
    (illness (keywords ?kw) (sickness ?sk))
    (while  (not (subsetp ?kw ?f )) 
        (bind ?f (askquestion "whot Does the plant seem to have ? ")))
=>   
    (assert ?sk))

我想做的只是简单地询问用户他们的工厂出了什么问题，并使用关键字来识别问题，然后断言问题。但是我不断收到以下错误。

Defining defrule: determineSickness 
[PRNTUTIL2] Syntax Error:  Check appropriate syntax for defrule.

ERROR:
(defrule MAIN::determineSickness
   (bind ?f (
FALSE
CLIPS> 

Answer 1

在 CLIPS 基本编程指南中有一个有效 CLIPS 语法的 BNF 规范。 defrules 的相关部分是：

<defrule-construct> ::=
   (defrule <rule-name> [<comment>] 
      [<declaration>]
      <conditional-element>*
      =>
      <action>*)

<action> ::= <expression>

<expression> ::= <constant> | <variable> | <function-call>

<function-call> ::= (<function-name> <expression>*)

<conditional-element> ::= 
   <pattern-CE> | 
   <assigned-pattern-CE> | 
   <not-CE> | 
   <and-CE> | 
   <or-CE> | 
   <logical-CE> |
   <test-CE> |
   <exists-CE> |
   <forall-CE>

规则的 when 部分（=> 之前的部分）包含必须与事实/实例匹配的条件，以便规则适用。您可以根据规则的条件进行函数调用，但不能使用您尝试过的语法。另外，由于条件可以以非顺序的顺序激活，因此必须在规则的动作中（=>之后的部分）指定必须顺序执行的程序代码。

您可以通过一些更改使您的原始代码在语法上正确：

(defrule determineSickness
    (illness (keywords $?kw) (sickness ?sk))
=>
    (bind ?f (askquestion "whot Does the plant seem to have ? "))
    (while  (not (member$ ?f ?kw)) 
        (bind ?f (askquestion "whot Does the plant seem to have ? ")))
    (assert (diagnosis ?sk)))

您的规则在语义上仍然不正确。这就是他们目前所做的：

For every illness, ask the user to specify one of the symptoms for that illness.

这是他们需要做的：

For every symptom specified by the user, find every illness having that symptom.