Incrementing a global variable within a user answered defrule

Question

I'm trying to increment a defglobal variable (symcount) by 1 if the user defines that they have pain by using the (read) function

(defrule QPain
         (initial-fact)
         =>
         (printout t "Are You In Pain? " crlf) 
         (bind (ans Answer) (read)) 
         )
(defrule AnsInc
         (Answ Answer = "y")
         =>
         (bind ?*symcount* (+ ?*symcount* 1)))

the increment must only happen of the user presses "y" otherwise the increment must not happen.

possible duplicate of [How to compare a global variable to a string in Clips?](http://stackoverflow.com/questions/30324191/how-to-compare-a-global-variable-to-a-string-in-clips) — Gary Riley, May 19 '15 at 16:31

score 0 · Accepted Answer · answered Nov 07 '15 at 17:22

CLIPS> (defglobal ?*symcount* = 0)
CLIPS> 
(defrule QPain
   =>
   (printout t "Are You In Pain? ") 
   (bind ?answer (read))
   (if (eq ?answer y)
      then
      (bind ?*symcount* (+ ?*symcount* 1))))
CLIPS> (reset)
CLIPS> (run)
Are You In Pain? y
CLIPS> ?*symcount*
1
CLIPS> (reset)
CLIPS> (run)
Are You In Pain? n
CLIPS> ?*symcount*
0
CLIPS>

Incrementing a global variable within a user answered defrule

1 Answers1