* http://cs.unibo.it/helm/.
*)
-(******************************************************************************)
-(* *)
-(* PROJECT HELM *)
-(* *)
-(* Ferruccio Guidi <fguidi@cs.unibo.it> *)
-(* 06/01/2003 *)
-(* *)
-(* *)
-(******************************************************************************)
-
+(* AUTOR: Ferruccio Guidi <fguidi@cs.unibo.it>
+ *)
val mql_true : MathQL.value
val set_union : 'a list -> 'a list -> 'a list
+val set_intersect : 'a list -> 'a list -> 'a list
+
val mql_union : ('a * 'b list) list -> ('a * 'b list) list ->
('a * 'b list) list