array reference gives invalid expression error

[williamwsmith]

Example of a simple rule below.
The console.log of the _domainValues[0] & [1] report correct values.
However when used in the constraint expression, the rules compiler reports
"Invalid expression". Any thoughts?

rule CheckAndAssertActualWeight {
    when {
            actualWeight_domain: ActualWeight_Domain {values: _domainValues};
            actualWeight_EnteredValue: ActualWeight_EnteredValue 
                (
                    actualWeight_EnteredValue.value >= _domainValues[0] &&
                    actualWeight_EnteredValue.value <= _domainValues[1]
                ) {value : _entered};
    }
    then {
        assert( new ActualWeight_Value({value:_entered}) );
        console.log("ActualWeight value assigned: %s", _entered);   
        console.log("ActualWeight domain %s %s.", _domainValues[0], _domainValues[1]);  
    }
}