(* David Goldberg, goldberg@parc.xerox.com, 1992 *)

INTERFACE Tree;

IMPORT Solve;

TYPE T = Solve.Tree;

PROCEDURE Equal (t, u: T): BOOLEAN;
PROCEDURE Copy (t: T): T;
PROCEDURE Compare (t, u: T): [-1 .. 1];
PROCEDURE Hash (t: T; lessThan: CARDINAL): CARDINAL;

END Tree.