public static function isValid(&$properties_dictionary, $limit_to_keys, &$error)
 {
     //	Check each property is valid
     //
     if (!parent::isValid($properties_dictionary, $limit_to_keys, $error)) {
         return false;
     }
     if (ValidationC::should_test_property(RANGE_POSITION, $properties_dictionary, true, $limit_to_keys) && !Range::propertyIsValid(RANGE_POSITION, $properties_dictionary[RANGE_POSITION], $error)) {
         //	Position was not valid
         //
         return false;
     }
     if (ValidationC::should_test_property(RANGE_LENGTH, $properties_dictionary, true, $limit_to_keys) && !Range::propertyIsValid(RANGE_LENGTH, $properties_dictionary[RANGE_LENGTH], $error)) {
         //	Range was not valid
         //
         return false;
     }
     return true;
 }