protected function _doList(&$content, array &$args = array(), $tag_type = 'unordered_list')
    {
        $items_content = '';

        // common arguments for all items
        $items_args = $this->_getArgsStack($args, 'items');

        // loop on each list items
        $i = 0;
        foreach ($content as $i=>$item_str) {
            $item_args = array_merge_recursive($items_args, $this->_getArgsStack($args, 'item'.$i));
            $items_content .= $this->_tagComposer($item_str, $tag_type.'_item', $item_args);
            $i++;
        }

        $content = $items_content;
    }