Chris@10: (*
Chris@10:  * Copyright (c) 1997-1999 Massachusetts Institute of Technology
Chris@10:  * Copyright (c) 2003, 2007-11 Matteo Frigo
Chris@10:  * Copyright (c) 2003, 2007-11 Massachusetts Institute of Technology
Chris@10:  *
Chris@10:  * This program is free software; you can redistribute it and/or modify
Chris@10:  * it under the terms of the GNU General Public License as published by
Chris@10:  * the Free Software Foundation; either version 2 of the License, or
Chris@10:  * (at your option) any later version.
Chris@10:  *
Chris@10:  * This program is distributed in the hope that it will be useful,
Chris@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
Chris@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Chris@10:  * GNU General Public License for more details.
Chris@10:  *
Chris@10:  * You should have received a copy of the GNU General Public License
Chris@10:  * along with this program; if not, write to the Free Software
Chris@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Chris@10:  *
Chris@10:  *)
Chris@10: 
Chris@10: type ('a, 'b) elem =
Chris@10:   | Leaf
Chris@10:   | Node of int * ('a, 'b) elem * ('a, 'b) elem * ('a * 'b) list
Chris@10: val empty : ('a, 'b) elem
Chris@10: val lookup :
Chris@10:     ('a -> int) -> ('a -> 'b -> bool) -> 'a -> ('b, 'c) elem -> 'c option
Chris@10: val insert :
Chris@10:     ('a -> int) -> 'a -> 'c -> ('a, 'c) elem -> ('a, 'c) elem