在 CLIPS 中定义 "anonymous" 规则

Question

我知道CLIPS中的规则通常使用defrule来命名。此规则称为 rule1:

(deftemplate animal (slot species))

(deffacts animal
  (animal (species dog)))

(defrule rule1
   (animal (species ?name))
   =>
   (printout t ?name crlf))
(reset)

(run)

(exit)
;

但是我还是不知道规则有没有必要命名。是否可以定义一个规则而不给它一个名字，像这样？

(deftemplate animal (slot species))

(deffacts animal
  (animal (species dog)))

(defrule
   (animal (species ?name))
   =>
   (printout t ?name crlf))
(reset)

(run)

(exit)
;

Answer 1

来自基本编程指南的第 5 部分：

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

需要规则名称。

要动态生成规则名称，请使用创建唯一符号的 gensym* 函数：

CLIPS> 
(deffunction create-anonymous (?conditions ?actions)
   (bind ?str (str-cat "(defrule " (gensym*) " "
                        ?conditions " => " ?actions ")"))
   (build ?str))
CLIPS> (deftemplate animal (slot species))
CLIPS> 
(create-anonymous "(animal (species ?name))"
                  "(printout t ?name crlf)")
TRUE
CLIPS> (rules)
gen1
For a total of 1 defrule.
CLIPS> (ppdefrule gen1)
(defrule MAIN::gen1
   (animal (species ?name))
   =>
   (printout t ?name crlf))
CLIPS>

在 CLIPS 中定义 "anonymous" 规则

Defining "anonymous" rules in CLIPS

clips