Source file `applicative.ml`

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module type Basic = Applicative_intf.Basic

module Make (A : Applicative_intf.Basic) = struct
  include A

  module O = struct
    let ( let+ ) x f = A.map x ~f
    let ( and+ ) = A.both

    let ( >>> ) x y =
      let+ () = x
      and+ y = y in
      y
    ;;
  end

  let rec all xs =
    match xs with
    | [] -> return []
    | x :: xs ->
      let open O in
      let+ x = x
      and+ xs = all xs in
      x :: xs
  ;;
end
[@@inline always]

module Id = struct
  include Make (struct
      type 'a t = 'a

      let return a = a
      let map x ~f = f x
      let both x y = x, y
    end)

  let all x = x
end