Re: [rules-users] facts hierarchy

wrote:

Hi, Is this what you are looking for? rule "A requires B" when $fact1: NodeFact(id == "A", selected == true, $b: b) $fact2: NodeFact(this == $b, selected == false, this DESCENDANT-OF $fact1) then $fact2.setSelected(true); end Best, 2010/5/7 Giovanni Motta <mottagio(a)gmail.com&gt; > Hi all, i have a question concerning facts hierarchy, i'm looking for some > hint as i suppose the same problem could have been faced by someone on the > list. > > I try to eplain with an example: > > - Suppose to have a tree of facts, each object representing an UI widget. > <root> > <A id="1"> > <B /> > </A> > <A id="2"> > <B /> > </A> > </root> > > - The individual elements A(1), B, A(2), B are mapped to facts, that are > inserted in a KnowledgeStatefulSession > - A rule exists that states that when an object A is selected, the B > object is automatically selected > - An event occurs that causes selection of node A(1) > > The expected result is, obviously, that only the B element that is > descendant of A(1) must be automatically selected > > I'm trying a way to express the 'descendant' relationship in LHS > construct. > The rule will look like: > > rule "A requires B" > when > $fact1: NodeFact(id == "A", selected == true) > $fact2: NodeFact(id == "B", selected == false, this DESCENDANT-OF $fact1) > then > $fact2.setSelected(true); > end > > > What is, in your opinion, the best way to handle this situation? What > should replace the fake "DESCENDANT-OF" match? > Do i need to use a function that returns the list of descendant nodes of > $fact1 and then match $fact2 against that? > Will this be fast when dealing with large trees? > > Any suggestion will be appreciated, thank you. > Giovanni > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > > -- XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Esteban Aliverti