protected void verifyOrdering( DynamicOperand operand ) {
if (operand instanceof PropertyValue) {
PropertyValue propValue = (PropertyValue)operand;
verifyOrdering(propValue.selectorName(), propValue.getPropertyName());
} else if (operand instanceof ReferenceValue) {
ReferenceValue value = (ReferenceValue)operand;
verifyOrdering(value.selectorName(), value.getPropertyName());
} else if (operand instanceof Length) {
Length length = (Length)operand;
verifyOrdering(length.getPropertyValue());
} else if (operand instanceof LowerCase) {
verifyOrdering(((LowerCase)operand).getOperand());