    /*
     * call-seq:
     *  [](tag_name)
     *
     * Get ElemementDescription for +tag_name+
     */
    static VALUE get_description(VALUE klass, VALUE tag_name)
    {
      const htmlElemDesc * description = htmlTagLookup(
          (const xmlChar *)StringValuePtr(tag_name)
      );

      if(NULL == description) return Qnil;
      return Data_Wrap_Struct(klass, 0, 0, (void *)description);
    }