Re: [rules-users] Evaluate rules for multiple facts of the same type within a StateuflSession

Hmm, it is very uncommon that I am solely addressed in a post where both me and the great Wolfgang Laune replied to. It is quite obvious that I have the lesser mind in this area. Anyway... There is a variety of ways to deal with it and it all depends on your use case. Salience is not the best way to go because it is difficult to manage and maintain in the ling run. Suppose that you would have 50 reductions and suppose that you would have to apply the reduction with the highest percentage (I am guessing that is the case in your example). IN this scenario, if you would add a 51th discount, that should be second in the prioritization order, you would have to adapt all saliences of the other rules to make it fit. This is not what you want. Also if you rely on saliences only, you might be impacted by other rules in other logical rule groups that also rely on salience only. If you must use salience and the amount of the reduction is the prioritization key, you could use the discount amount as the salience value. If there is any other kind of rule sequence, make sure it is done nice and tidy. Only rely on salience within the groups, not accross. An other approach is that you decouple the validity checking of the reduction from applying the reduction. rule agenda-group "discount eligibility" when ... then insert new Discount(code?, amount?, shoppingCart) rule agenda-group "apply discounts" when $cart: ShoppingCart() not DiscountApplied(cart == $cart) $myDisc: Discount() not Discount(amount > $myDisc.amount) then cart.setDiscount($myDisc.getAmount()); insert(new DiscountApplied()); end This implies that setDiscount knows how to process the discount. You might need different extensions of Discount to fulfill all your needs. Regards, Frank pdario wrote -- View this message in context: http://drools.46999.n3.nabble.com/Evaluate-rules-for-multiple-facts-of-th... Sent from the Drools: User forum mailing list archive at Nabble.com.