在剪辑中断言字符串

Question

我试图将name的值断言到变量中，但是当我断言它时，这个值是以引号形式出现的，并且在末尾还有一个额外的空间。

   (defrule discount_amt_group 
    (exists (Student (age 14)(marks ?q&:(> ?q 40))))
    =>
    (bind ?name "")
    (do-for-all-facts ((?p Student))
                  (or (eq ?p:marks 80)
                     (eq ?p:marks 75)
                     (eq ?p:marks 90))
    (bind ?name (str-cat ?name ?p:name " "))
    (bind ?totalMarks (+ ?totalMarks ?p:marks)))
    (assert (StudOut(names ?name)))

期望值将是(名为哈利·罗恩·金格)，但现在它将以“哈利·罗恩·金格”的名字出现，请提出建议。

Answer 1

将名称表示为多字段值，而不是字符串。您可以使用create$函数最初创建一个空的多字段值，然后再向其追加值。

         CLIPS (6.31 6/12/19)
CLIPS> 
(deftemplate Student
   (slot name)
   (slot age)
   (slot marks))
CLIPS>    
(deftemplate StudOut
   (multislot names)
   (slot totalMarks))
CLIPS>    
(deffacts Students
   (Student (name Harry) (age 14) (marks 80))
   (Student (name Ron) (age 15) (marks 75))
   (Student (name Ginger) (age 14) (marks 90))
   (Student (name Sally) (age 12) (marks 95)))
CLIPS>    
(defrule discount_amt_group 
   (exists (Student (age 14)(marks ?q&:(> ?q 40))))
   =>
   (bind ?name (create$))
   (bind ?totalMarks 0)
   (do-for-all-facts ((?p Student))
                     (or (eq ?p:marks 80)
                         (eq ?p:marks 75)
                         (eq ?p:marks 90))
      (bind ?name (create$ ?name ?p:name))
      (bind ?totalMarks (+ ?totalMarks ?p:marks)))
   (assert (StudOut (names ?name)
                    (totalMarks ?totalMarks))))
CLIPS> (reset)
CLIPS> (run)
CLIPS> (facts)
f-0     (initial-fact)
f-1     (Student (name Harry) (age 14) (marks 80))
f-2     (Student (name Ron) (age 15) (marks 75))
f-3     (Student (name Ginger) (age 14) (marks 90))
f-4     (Student (name Sally) (age 12) (marks 95))
f-5     (StudOut (names Harry Ron Ginger) (totalMarks 245))
For a total of 6 facts.
CLIPS>