Over_arrow.Req
type ('a, 'b) t = ('a, 'b) Arrow.t
The type held by the Arrow_zero.
Arrow_zero
val neutral : ('a, 'b) t
The neutral element of the Arrow_zero.
val combine : ('a, 'b) t -> ('a, 'b) t -> ('a, 'b) t
Combine two values of ('a, 'b) t into one.
('a, 'b) t