--- /dev/null
+/* PSPP - computes sample statistics.
+ Copyright (C) 2007 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301, USA. */
+
+#ifndef DATA_CASEGROUPER_H
+#define DATA_CASEGROUPER_H 1
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct case_ordering;
+struct casereader;
+struct ccase;
+struct dictionary;
+struct variable;
+
+struct casegrouper *
+casegrouper_create_func (struct casereader *,
+ bool (*same_group) (const struct ccase *,
+ const struct ccase *,
+ void *aux),
+ void (*destroy) (void *aux),
+ void *aux);
+struct casegrouper *casegrouper_create_vars (struct casereader *,
+ struct variable *const *vars,
+ size_t var_cnt);
+struct casegrouper *casegrouper_create_splits (struct casereader *,
+ const struct dictionary *);
+struct casegrouper *casegrouper_create_case_ordering (struct casereader *,
+ const struct case_ordering *);
+bool casegrouper_get_next_group (struct casegrouper *, struct casereader **);
+bool casegrouper_destroy (struct casegrouper *);
+
+#endif /* data/casegrouper.h */