Nope, MVEL 2 is not backward compatible with the 1.3.x release.

   I am talking with Mike about this.

   []s
   Edson

2008/12/16 Olivier THIERRY <olivier.thierry@gmail.com>
Sorry, I had not seen there was later version than 1.3.9.
Anyway, I tried with 1.3.12 and had the same problem.
>From 1.3.13, it looks like there is a problem on mvel initialization
since I have this stack trace :

java.lang.NoSuchMethodError: org.mvel.MVEL.setThreadSafe(Z)V
       at org.drools.rule.builder.dialect.mvel.MVELDialect.init(MVELDialect.java:144)
       at org.drools.compiler.DialectRegistry.initAll(DialectRegistry.java:49)
       at org.drools.compiler.PackageBuilder.<init>(PackageBuilder.java:146)
       at org.drools.compiler.PackageBuilder.<init>(PackageBuilder.java:86)
       at t4.test.drools.TestRuleBase.executeRuleWithDsl(TestRuleBase.java:105)
       at t4.test.drools.Test1.testDslMvel(Test1.java:39)



2008/12/16 Olivier THIERRY <olivier.thierry@gmail.com>:
> I use mvel 1.3.9, so the latest 1.3.x version.
> Is there a way to upgrade to mvel 2.x with drools 4.0.7 ? Or will I
> have to wait for drools 5.0.0 ?
>
> 2008/12/15 Edson Tirelli <tirelli@post.com>:
>>
>>    BTW, what version of MVEL are you using?
>>
>> 2008/12/15 Olivier THIERRY <olivier.thierry@gmail.com>
>>>
>>> Well ... I found something very strange with Drools and mvel dialect
>>> ... It looks like Drools doesn't like points in function parameters !
>>>
>>> I made this very simple test with a log function and the easier rule
>>> you can have :
>>>
>>> function void log (String message) {
>>>        System.out.println(message);
>>> }
>>>
>>> rule "test"
>>>        no-loop
>>>        when
>>>                eval(true)
>>>        then
>>>                log("hello world")
>>> end
>>>
>>> log("hello world") works ok
>>> log("hello.world") (note the point) fails with this stack trace :
>>>
>>> org.drools.spi.ConsequenceException:
>>> org.mvel.UnresolveablePropertyException: unable to resolve token:
>>> log("hello.world")
>>>        at
>>> org.drools.base.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:13)
>>>        at
>>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:558)
>>>        at
>>> org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:518)
>>>        at
>>> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:475)
>>>        at
>>> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:439)
>>>        at t4.test.drools.TestRuleBase.executeRule(TestRuleBase.java:44)
>>>        at t4.test.drools.Test1.testDebug(Test1.java:57)
>>> Caused by: org.mvel.UnresolveablePropertyException: unable to resolve
>>> token: log("hello.world")
>>>        at
>>> org.mvel.ast.PropertyASTNode.initializePropertyNode(PropertyASTNode.java:129)
>>>        at
>>> org.mvel.ast.PropertyASTNode.getReducedValueAccelerated(PropertyASTNode.java:24)
>>>        at org.mvel.MVELRuntime.execute(MVELRuntime.java:90)
>>>        at
>>> org.mvel.CompiledExpression.getValue(CompiledExpression.java:111)
>>>        at org.mvel.MVEL.executeExpression(MVEL.java:235)
>>>        at
>>> org.drools.base.mvel.MVELConsequence.evaluate(MVELConsequence.java:48)
>>>        at
>>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:554)
>>>        ... 34 more
>>>
>>> It looks like there is a problem with point character, doesn't it ? Is
>>> it a known problem ?
>>>
>>> Regards,
>>>
>>> Olivier
>>>
>>>
>>> 2008/12/15 Olivier THIERRY <olivier.thierry@gmail.com>:
>>> > Thanks Edson. Here it is :
>>> >
>>> > rule "CALCUL_RELICAT_CP"
>>> >        salience 8
>>> >        no-loop
>>> >        when
>>> >                not $RELICAT_CP : VOCounter (code=="RELICAT_CP")
>>> >                $startDate : RuleDate(name=="startDate")
>>> >                $endDate : RuleDate(name=="endDate")
>>> >                $SOLDE_CP_CUM : VOCounter ( code=="SOLDE_CP_CUM",
>>> > startDate.year == ($startDate.year - 1) )
>>> >        then
>>> >                VOCounter $relicat =
>>> > createCounter(drools,"RELICAT_CP",$SOLDE_CP_CUM.value);
>>> >                insert($relicat);
>>> >
>>> >  insert(createCounter(drools,"SOLDE_RELICAT_CP",$SOLDE_CP_CUM.value));
>>> > end
>>> >
>>> > I thought about trying with a newer version of mvel, but it doesn't
>>> > look so easy to upgrade it :(
>>> >
>>> > 2008/12/15 Edson Tirelli <tirelli@post.com>:
>>> >>
>>> >>      Can you plz show us the DRL instead of the DSLR for your rule? use
>>> >> the
>>> >> DRLViewer tab for that...
>>> >>
>>> >> 2008/12/15 Olivier THIERRY <olivier.thierry@gmail.com>
>>> >>>
>>> >>> Hi,
>>> >>>
>>> >>> I use drools 4.0.7 and I encounter a problem calling a function from a
>>> >>> rule written for mvel dialect.
>>> >>>
>>> >>> The function I need to call has this signature :
>>> >>>
>>> >>> function VOCounter createCounter(org.drools.spi.KnowledgeHelper
>>> >>> drools, String code, Number number)
>>> >>>
>>> >>> When I call this function, I want to assign result to a variable, for
>>> >>> example to insert it to working memory later, or just to use it in
>>> >>> another function call.
>>> >>> So I wrote something like that (I am writing a DSL so part of the code
>>> >>> is
>>> >>> DSL ):
>>> >>>
>>> >>> rule "CALCUL_RELICAT_CP"
>>> >>>        salience 8
>>> >>>        no-loop
>>> >>>        when
>>> >>>                not There is a counter called "RELICAT_CP"
>>> >>>                There is a date called "startDate"
>>> >>>                There is a date called "endDate"
>>> >>>                There is a counter called "SOLDE_CP_CUM" with
>>> >>>                        - start date is last year
>>> >>>        then
>>> >>> >               VOCounter $relicat =
>>> >>> > createCounter(drools,"RELICAT_CP",$SOLDE_CP_CUM.value);
>>> >>> >               insert($relicat);
>>> >>>                Copy counter $SOLDE_CP_CUM to SOLDE_RELICAT_CP
>>> >>> end
>>> >>>
>>> >>> But I have the following stack trace :
>>> >>>
>>> >>> org.drools.spi.ConsequenceException:
>>> >>> org.mvel.UnresolveablePropertyException: unable to resolve token:
>>> >>> createCounter(drools,"RELICAT_CP",$SOLDE_CP_CUM.value)
>>> >>>        at
>>> >>>
>>> >>> org.drools.base.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:13)
>>> >>>        at
>>> >>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:558)
>>> >>>        at
>>> >>> org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:518)
>>> >>>        at
>>> >>>
>>> >>> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:475)
>>> >>>        at
>>> >>>
>>> >>> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:439)
>>> >>>        at
>>> >>>
>>> >>> fr.horoquartz.t4.test.drools.TestRuleBase.executeRuleWithDsl(TestRuleBase.java:120)
>>> >>>        at fr.horoquartz.t4.test.drools.Test1.testDsl(Test1.java:39)
>>> >>> Caused by: org.mvel.UnresolveablePropertyException: unable to resolve
>>> >>> token: createCounter(drools,"RELICAT_CP",$SOLDE_CP_CUM.value)
>>> >>>        at
>>> >>>
>>> >>> org.mvel.ast.PropertyASTNode.initializePropertyNode(PropertyASTNode.java:129)
>>> >>>        at
>>> >>>
>>> >>> org.mvel.ast.PropertyASTNode.getReducedValueAccelerated(PropertyASTNode.java:24)
>>> >>>        at
>>> >>> org.mvel.ExecutableAccessor.getValue(ExecutableAccessor.java:45)
>>> >>>        at
>>> >>>
>>> >>> org.mvel.ast.TypedVarNode.getReducedValueAccelerated(TypedVarNode.java:43)
>>> >>>        at org.mvel.MVELRuntime.execute(MVELRuntime.java:90)
>>> >>>        at
>>> >>> org.mvel.CompiledExpression.getValue(CompiledExpression.java:111)
>>> >>>        at org.mvel.MVEL.executeExpression(MVEL.java:235)
>>> >>>        at
>>> >>> org.drools.base.mvel.MVELConsequence.evaluate(MVELConsequence.java:48)
>>> >>>        at
>>> >>> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:554)
>>> >>>        ... 34 more
>>> >>>
>>> >>> What is strange is that it works if I don't assign function call
>>> >>> result to a variable. For example the following works  :
>>> >>>
>>> >>> insert (createCounter(drools,"RELICAT_CP",$SOLDE_CP_CUM.value));
>>> >>>
>>> >>> It also works if I assign $SOLDE_CP_CUM.value to a temporary variable
>>> >>> and use it for function call :
>>> >>>
>>> >>> Number $val = $SOLDE_CP_CUM.value;
>>> >>> VOCounter $relicat = createCounter(drools,"RELICAT_CP",$val);
>>> >>> insert($relicat);
>>> >>>
>>> >>> I had not this problem using java dialect. I understand nothing in
>>> >>> what happens ... Anyone has an idea what the problem is ?
>>> >>>
>>> >>> Thanks in advance,
>>> >>>
>>> >>> Olivier
>>> >>> _______________________________________________
>>> >>> rules-users mailing list
>>> >>> rules-users@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
>>> >>
>>> >> _______________________________________________
>>> >> rules-users mailing list
>>> >> rules-users@lists.jboss.org
>>> >> https://lists.jboss.org/mailman/listinfo/rules-users
>>> >>
>>> >>
>>> >
>>> >
>>> >
>>> > --
>>> > Seules 2 choses sont infinies : l'univers et la bêtise humaine ; et
>>> > encore pour l'univers, je ne suis pas sûr … (Einstein)
>>> >
>>>
>>>
>>>
>>> --
>>> Seules 2 choses sont infinies : l'univers et la bêtise humaine ; et
>>> encore pour l'univers, je ne suis pas sûr … (Einstein)
>>>
>>> _______________________________________________
>>> rules-users mailing list
>>> rules-users@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
>>
>> _______________________________________________
>> rules-users mailing list
>> rules-users@lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/rules-users
>>
>>
>
>
>
> --
> Seules 2 choses sont infinies : l'univers et la bêtise humaine ; et
> encore pour l'univers, je ne suis pas sûr … (Einstein)
>



--
Seules 2 choses sont infinies : l'univers et la bêtise humaine ; et
encore pour l'univers, je ne suis pas sûr … (Einstein)

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--
 Edson Tirelli
 JBoss Drools Core Development
 JBoss, a division of Red Hat @ www.jboss.com