# Module type Either_intf.Focused

    module type Focused = sig .. end

Many functions in `Either` focus on just one constructor. The `Focused` signature abstracts over which constructor is the focus. To use these functions, use the `First` or `Second` modules in `S`.

    type (+'focus, +'other) t

    include Monad.S2

    include Applicative.S2

    include Container.S1_phantom

    module Args: Applicative.Args2  with type ('a, 'e) arg := ('a, 'e) t

    val value : ('a, 'b) t -> default:'a -> 'a

    val to_option : ('a, 'b) t -> 'a option

    val with_return : ('a With_return.return -> 'b) -> ('a, 'b) t

    val combine : ('a, 'd) t ->
           ('b, 'd) t ->
           f:('a -> 'b -> 'c) ->
           other:('d -> 'd -> 'd) -> ('c, 'd) t

    val combine_all : ('a, 'b) t list ->
           f:('b -> 'b -> 'b) -> ('a list, 'b) t

    val combine_all_unit : (unit, 'b) t list ->
           f:('b -> 'b -> 'b) -> (unit, 'b) t