    /*
     * call-seq:
     *   prefix
     *
     * Get the shorthand reference to the namespace associated with the node.
     */
    static VALUE prefix(VALUE self)
    {
      xmlTextReaderPtr reader;
      const char *prefix;

      Data_Get_Struct(self, xmlTextReader, reader);
      prefix = (const char *)xmlTextReaderConstPrefix(reader);
      if(prefix == NULL) return Qnil;

      return NOKOGIRI_STR_NEW2(prefix);
    }