On Mar 1, 2007, at 4:01 PM, Mrinal Khanvilkar wrote:
Hi,
Does anyone know how to catch exceptions in a RULE .
I mean like
(defrule someRule
"comment"
(Callhome (thing1 ?a)(thing2 ?b))
(try (< ?a ?b)catch (printout t "they need to be integers" crlf))
(test(eq ?b TRUE))
=>
(printout t "done" crlf)
)
in the above case the engine throws me an exception when ?a and ?b
happen to be strings and then it doesnt fire the remaining rules.
i dont want that. Instead i would want the engine to just ignore
this rule if ?a ?b are strings.
can this be done.?
You'd have to put that "try" statement into a "test" conditional
element, just like any other function call that's outside a pattern.
Just make sure you return FALSE from the catch block, and it will
halt pattern matching. Just something like
(test (try
(< ?a ?b)
catch
(printout t "they need to be integers" crlf)
FALSE))
ought to work fine.
---------------------------------------------------------
Ernest Friedman-Hill
Advanced Software Research Phone: (925) 294-2154
Sandia National Labs FAX: (925) 294-2234
PO Box 969, MS 9012 [EMAIL PROTECTED]
Livermore, CA 94550 http://www.jessrules.com
--------------------------------------------------------------------
To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]'
in the BODY of a message to [EMAIL PROTECTED], NOT to the list
(use your own address!) List problems? Notify [EMAIL PROTECTED]
--------------------------------------------------------------------
