val compare :
('a -> 'a -> int) ->
('b -> 'b -> int) ->
('a, 'b) t ->
('a, 'b) t ->
int
val order :
('a -> 'a -> order) ->
('b -> 'b -> order) ->
('a, 'b) t ->
('a, 'b) t ->
order
val equal :
('a -> 'a -> bool) ->
('b -> 'b -> bool) ->
('a, 'b) t ->
('a, 'b) t ->
bool
val pp : 'a pp -> 'b pp -> ('a, 'b) t pp
val hash : ('a -> int) -> ('b -> int) -> ('a, 'b) t -> int