- while (casereader_peek (grouper->reader, 0, &tmp)
- && grouper->same_group (&group_case, &tmp, grouper->aux))
+ casewriter_write (writer, case_ref (group_case));
+
+ while ((tmp = casereader_peek (grouper->reader, 0)) != NULL
+ && grouper->same_group (group_case, tmp, grouper->aux))