Drools 5.3.0 FINAL.

This experiment was inspired by code posted with the insinuation that MVEL would "optimize" condition evaluation. - Consider this rule:

rule "Term - java"
dialect "java"
when
$ea : EasyApp( Test.valueInList( $ea.getProductCode(), "CAR" )==true
&& age < 0 )
then end

You'd expect that Test.valueInList() is called once per inserted EasyApp fact, and this can be verified easily. - Now the same rule, with MVEL's syntactic sugar:

rule "Term - mvel"
dialect "mvel"
when
$ea : EasyApp( Test.valueInList( productCode, "CAR" )==true
&& age < 0 )
then end

Now Test.valueInList() is called twice for each inserted fact.

Cheers
Wolfgang