/*
 *  call-seq:
 *     searcher.doc_freq(field, term) -> integer
 *
 *  Return the number of documents in which the term +term+ appears in the
 *  field +field+.
 */
static VALUE
frt_sea_doc_freq(VALUE self, VALUE rfield, VALUE rterm)
{
    GET_SEA();
    return INT2FIX(sea->doc_freq(sea,
                                 frt_field(rfield),
                                 StringValuePtr(rterm)));
}