Closed.LAWS
type ('a, 'b) t
val closed_1 : unit -> ('a -> 'b, ('c, 'd) t -> ('b -> 'c, 'a -> 'd) t) Law.t
val closed_2 : unit -> (('a, 'b) t, ('c -> 'd -> 'a, 'c -> 'd -> 'b) t) Law.t
val closed_3 : unit -> (('a, 'b) t, ('a, 'b) t) Law.t