JESS: accumulate on backchain-reactive facts/need-facts

[yuping he]

Hi, I am just curious are there any specific reasons that accumulate won't
work with backchain-reactive facts or
any facts that simply starts with pattern (need-???)


(

(clear)
(reset)
(watch all)

(deffacts myfacts (need-xyz))

(reset)

(defrule rule
?count <- (accumulate
 (bind ?c 0)
 (bind ?c (+ ?c 1))
 ?c
 (MAIN::need-xyz)
 )
=>
(printout t "count: " ?count crlf)
)

Jess> Unexpected exception:
null