[rules-users] rule chaining problem?
Hi everyone,
I have this scenario:
A diagram with nodes and arcs between them.
I'm willing to control the visual elements with rules.
Nodes are asserted at the moment of insertion.
Object node = new AnyObject() ;
FactHandle hNode = workingMemory.assertObject( node ) ;
Nodes are retracted from working memory when are deleted from the diagram.
workingMemory.retractObject( hNode ) ;
Arcs can not exist in the diagram if any of the related nodes no longer
exists.
So I must have a rule that keeps consistency in the diagram, something like:
## to illustrate the problem just checking source
rule "Delete no longer valid arcs"
when
a : Arc(s: source, tag, t: target)
not s: Object()
then
retract(a) ;
end
But the rule is not working, help is much appreciated
Regards,
Gerardo Segura