CLIPS LHS match multislot

Question

I wrote this rule for an expert system :

    (defrule wild chicory
      (attribute (name habitat) (value sea montain grassland unknown))   
=>
      (assert (plant "Cichorium_Intybus"))
    )

However I don't want the habitat's value to match all of the values that I have given, but to only match at least one of values. I'm wondering how I should do this. I could do it so:

(defrule wild chicory
          (or (attribute (name habitat) (value sea)) 
              (attribute (name habitat) (value mountain))
              (attribute (name habitat) (value grassland))
              (attribute (name habitat) (value unknow))
          )
          =>
          (assert (plant "Cichorium_Intybus"))
)

But I would like to know if there is a better solution. Thanks

score 3 · Accepted Answer · answered Aug 30 '16 at 23:35

If value is a single field slot, do it this way:

(defrule wild chicory
  (attribute (name habitat) (value sea | mountain | grassland | unknown)) 
  =>
  (assert (plant "Cichorium_Intybus")))

If value is a multi field slot, do it this way:

(defrule wild chicory
  (attribute (name habitat) (value $? sea | mountain | grassland | unknown $?)) 
  =>
  (assert (plant "Cichorium_Intybus")))

CLIPS LHS match multislot

1 Answers1