--- /dev/null
+(* virt-similarity
+ * Copyright (C) 2013 Red Hat 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.
+ *)
+
+(** Cladograms. *)
+
+type t =
+ | Leaf of int (** A single disk image (index of). *)
+ | Node of t list (** An interior node in the tree. *)
+
+val images_in_subtree : t -> int list
+
+val format_cladogram : ?format_leaf:(int -> string) -> t -> string list