/*
 *  call-seq:
 *     index_reader.term_positions_for(field, term) -> TermDocEnum
 *
 *  Same as IndexReader#term_docs_for(field, term) except the TermDocEnum will
 *  also allow you to scan through the positions at which a term occurs. See
 *  TermDocEnum for more info.
 */
static VALUE
frt_ir_t_pos_for(VALUE self, VALUE rfield, VALUE rterm)
{
    IndexReader *ir = (IndexReader *)DATA_PTR(self);
    return frt_get_tde(self, ir_term_positions_for(ir,
                                                   frt_field(rfield),
                                                   StringValuePtr(rterm)));
}