我如何与剪辑中的 nil 进行比较?
我试过了
(defrule update-time
?cur-time <- (current-time ?time)
(order (event-time ?new-time-o&:(neq ?new-time-o nil)))
我也试过
(neq ?new-time-o "nil")
它似乎都不起作用,我没有激活。