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12.16.1.21 Getting the Cardinality for a Slot

This function groups the minimum and maximum cardinality allowed for a multifield slot into a multifield variable. A maximum cardinality of infinity is indicated by the symbol +oo (the plus character followed by two lowercase oísónot zeroes). A multifield of length zero is returned for single field slots or if an error occurs.

Syntax

(slot-cardinality <class-name> <slot-name>)

Example

CLIPS> (clear)
CLIPS>
(defclass A (is-a USER)
  (slot x)
  (multislot y (cardinality ?VARIABLE 5))
  (multislot z (cardinality 3 ?VARIABLE)))
CLIPS> (slot-cardinality A x)
()
CLIPS> (slot-cardinality A y)
(0 5)
CLIPS> (slot-cardinality A z)
(3 +oo)
CLIPS>


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