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12.16.1.23 Getting the Numeric Range for a Slot

This function groups the minimum and maximum numeric ranges allowed a slot into a multifield variable. A minimum value of infinity is indicated by the symbol oo (the minus character followed by two lowercase oísónot zeroes). A maximum value of infinity is indicated by the symbol +oo (the plus character followed by two lowercase oísónot zeroes). The symbol FALSE is returned for slots in which numeric values are not allowed. A multifield of length zero is returned if an error occurs.

Syntax

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

Example

CLIPS> (clear)
CLIPS>
(defclass A (is-a USER)
  (slot x)
  (slot y (type SYMBOL))
  (slot z (range 3 10)))
CLIPS> (slot-range A x)
(-oo +oo)
CLIPS> (slot-range A y)
FALSE
CLIPS> (slot-range A z)
(3 10)
CLIPS>


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