Via_dimap_and_left.Req
type ('a, 'b) t
The type held by the Choice Profunctor.
Choice Profunctor
val dimap : ('a -> 'b) -> ('c -> 'd) -> ('b, 'c) t -> ('a, 'd) t
val left : ('a, 'b) t -> (('a, 'c) Stdlib.Either.t, ('b, 'c) Stdlib.Either.t) t
Act on the left parameter of the sum.