[rules-users] first steps with drools.....first errors

[Edson Tirelli]

   You syntax is wrong. Fixing your syntax is as easy as saying:

exists ExamDetail( authLimit != null )

   But I think that your rules can be simplified by simply writing:

rule "Rule n.1"
dialect "mvel"
no-loop true
salience 10
   when
       $examDetail : ExamDetail( $value: value < authLimit);
   then
       System.out.println( "1 Exam passed!" + $value);
end

rule "Rule n.2"
dialect "mvel"
no-loop true
salience 10
   when
       not ExamDetail( value < authLimit );
   then
       System.out.println( "2 Exam passed! + $value);
end


   This should cover both of your scenarios.

   []s
   Edson

2008/9/12 Nicola Benaglia <nicola.benaglia at tecno-progetti.eu>

> Hi,
> I am moving my first steps with Drools 4.0.7.
>
> In my case I have an exam result to valuate.
> I can pass an ExamDetailas fact containing (value, authLimit, lawLimit)
> where authLimit may or may not be present.
>
> How can I force to valuate a rule only if a property exists?
>
> Here an example:
>
> rule "Rule n.1"
> dialect "mvel"
> no-loop true
> salience 10
>    when
>         exists ExamDetail(authLimit);
>        $examDetail : ExamDetail( $value: value < authLimit);
>    then
>        System.out.println( "1 Exam passed!" + $value);
> end
>
> rule "Rule n.2"
> dialect "mvel"
> no-loop true
> salience 10
>    when
>        not exists ExamDetail(authLimit);
>        ExamDetail( $value: value < lawLimit);
>    then
>        System.out.println( "2 Exam passed! + $value);
> end
>
>
> With these 2 rules I expected to cover my 2 cases:
> 1) When I have authLimit  --> rule #1
> 2) When authLimit is absent --> rule #2
>
> But I get this error (when I don't have authlimit):
>
> Exception in thread "main" org.drools.rule.InvalidRulePackage: [14,21]:
> unknown:14:21 Unexpected token 'authLimit'[25,6]: unknown:25:6
> Unexpected token 'exists'[25,24]: unknown:25:24 Unexpected token
> 'authLimit'
>    at org.drools.rule.Package.checkValidity(Package.java:424)
>    at
> org.drools.common.AbstractRuleBase.addPackage(AbstractRuleBase.java:394)
>    at eu.tecnoprogetti.rules.seam.ExamCheck.main(ExamCheck.java:23)
>
>
> Any suggestions?
> Thank you for your time.
> Nico
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>



-- 
Edson Tirelli
JBoss Drools Core Development
JBoss, a division of Red Hat @ www.jboss.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20080916/9210d550/attachment.html