/*
 * call-seq:
 *   lang
 *
 * Get the xml:lang scope within which the node resides.
 */
static VALUE lang(VALUE self)
{
  xmlTextReaderPtr reader;
  Data_Get_Struct(self, xmlTextReader, reader);
  const char * lang = (const char *)xmlTextReaderConstXmlLang(reader);
  if(lang == NULL) return Qnil;

  return rb_str_new2(lang);
}