Hi,
Don't know if this is what you are looking for, but in Jess, null is
represented as nil (inherited from CLIPS).
http://www.jessrules.com/jess/docs/71/basics.html
Try this out:
(deftemplate foo
(slot bar)
(slot qwe) )
(defrule r
?f <- (foo (qwe nil))
=>
(printout t "Got a
Are you talking about whether the slot is "nil" or not? You can just
do:
(some-slot nil)
to match for an empty slot or
(some-slot ~nil)
to match a non-empty slot
On Oct 30, 2008, at 7:58 AM, David Coyle wrote:
Hello:
I'm working with objects that have numerous relationships to others.
Th
Hello:
I'm working with objects that have numerous relationships to others.
There are a number of times where I need to simply check whether a
particular relationship is or is not null, without caring about the
actual destination object itself.
I haven't found an appropriate function: does one
