protected function get_yui3lib_headcode() {
        global $CFG;

        $jsrev = $this->get_jsrev();

        $yuiformat = '-min';
        if ($this->yui3loader->filter === 'RAW') {
            $yuiformat = '';
        }

        $format = '-min';
        if ($this->YUI_config->groups['moodle']['filter'] === 'DEBUG') {
            $format = '-debug';
        }

        $rollupversion = $CFG->yui3version;
        if (!empty($CFG->yuipatchlevel)) {
            $rollupversion .= '_' . $CFG->yuipatchlevel;
        }

        $baserollups = array(
            'rollup/' . $rollupversion . "/yui-moodlesimple{$yuiformat}.js",
        );

        if ($this->yui3loader->combine) {
            return '<script type="text/javascript" src="' .
                    $this->yui3loader->local_comboBase .
                    implode('&amp;', $baserollups) .
                    '"></script>';
        } else {
            $code = '';
            foreach ($baserollups as $rollup) {
                $code .= '<script type="text/javascript" src="'.$this->yui3loader->local_comboBase.$rollup.'"></script>';
            }
            return $code;
        }

    }