/*
 *  call-seq:
 *     iw.term_index_interval = term_index_interval -> term_index_interval
 *
 *  Set the term_index_interval parameter
 */
static VALUE
frt_iw_set_index_interval(VALUE self, VALUE rval)
{
    IndexWriter *iw = (IndexWriter *)DATA_PTR(self);
    iw->config.index_interval = FIX2INT(rval);
    return rval;
}