dialect "mvel"

rule "rule_multiply"
    when
        $fact : Fact( $bd: bd, bd2 == $bd * -1)
    then
        System.out.println("***** $fact = "+$fact);
end

Execution default-generateModel of goal org.kie:kie-maven-plugin:7.59.0.Final-redhat-00009:generateModel failed: [
com/example/reproducer/PCD/LambdaExtractorCD1B6E5C7CFD387685758203C8EB22B1.java (25:858) : The operator * is undefined for the argument type(s) BigDecimal, int,
com/example/reproducer/PF0/LambdaPredicateF08177C575A8F93768627585DF0FD322.java (25:1107) : The operator * is undefined for the argument type(s) BigDecimal, int]

public enum LambdaExtractorCD1B6E5C7CFD387685758203C8EB22B1 implements org.drools.model.functions.Function1<java.math.BigDecimal, java.lang.Object>, org.drools.model.functions.HashedExpression {
 ...
    @Override()
    public java.lang.Object apply(java.math.BigDecimal $bd) {
        return $bd * -1;
    }
}