public static function get_ruleoutcome_name($ruleoutcome) {

        switch ($ruleoutcome) {
            case self::OUTCOME_NONE:
                $strname = 'none';
                break;
            case self::OUTCOME_EVIDENCE:
                $strname = 'evidence';
                break;
            case self::OUTCOME_RECOMMEND:
                $strname = 'recommend';
                break;
            case self::OUTCOME_COMPLETE:
                $strname = 'complete';
                break;
            default:
                throw new \moodle_exception('errorcompetencyrule', 'core_competency', '', $ruleoutcome);
                break;
        }

        return new lang_string('coursemodulecompetencyoutcome_' . $strname, 'core_competency');
    }