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open! Import
module List = List0
include Monad_intf
module type Basic_general = sig
type ('a, 'i, 'j, 'd, 'e) t
val bind
: ('a, 'i, 'j, 'd, 'e) t
-> f:('a -> ('b, 'j, 'k, 'd, 'e) t)
-> ('b, 'i, 'k, 'd, 'e) t
val map
: [ `Define_using_bind
| `Custom of ('a, 'i, 'j, 'd, 'e) t -> f:('a -> 'b) -> ('b, 'i, 'j, 'd, 'e) t
]
val return : 'a -> ('a, 'i, 'i, 'd, 'e) t
end
module Make_general (M : Basic_general) = struct
let bind = M.bind
let return = M.return
let map_via_bind ma ~f = M.bind ma ~f:(fun a -> M.return (f a))
let map =
match M.map with
| `Define_using_bind -> map_via_bind
| `Custom x -> x
;;
module Monad_infix = struct
let ( >>= ) t f = bind t ~f
let ( >>| ) t f = map t ~f
end
include Monad_infix
module Let_syntax = struct
let return = return
include Monad_infix
module Let_syntax = struct
let return = return
let bind = bind
let map = map
let both a b = a >>= fun a -> b >>| fun b -> a, b
module Open_on_rhs = struct end
end
end
let join t = t >>= fun t' -> t'
let ignore_m t = map t ~f:(fun _ -> ())
let all =
let rec loop vs = function
| [] -> return (List.rev vs)
| t :: ts -> t >>= fun v -> loop (v :: vs) ts
in
fun ts -> loop [] ts
;;
let rec all_unit = function
| [] -> return ()
| t :: ts -> t >>= fun () -> all_unit ts
;;
end
module Make_indexed (M : Basic_indexed) :
S_indexed with type ('a, 'i, 'j) t := ('a, 'i, 'j) M.t = Make_general (struct
include M
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'i, 'j) M.t
end)
module Make3 (M : Basic3) : S3 with type ('a, 'd, 'e) t := ('a, 'd, 'e) M.t =
Make_general (struct
include M
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'd, 'e) M.t
end)
module Make2 (M : Basic2) : S2 with type ('a, 'd) t := ('a, 'd) M.t = Make_general (struct
include M
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'd) M.t
end)
module Make (M : Basic) : S with type 'a t := 'a M.t = Make_general (struct
include M
type ('a, 'i, 'j, 'd, 'e) t = 'a M.t
end)
module Of_monad_general (Monad : sig
type ('a, 'i, 'j, 'd, 'e) t
val bind
: ('a, 'i, 'j, 'd, 'e) t
-> f:('a -> ('b, 'j, 'k, 'd, 'e) t)
-> ('b, 'i, 'k, 'd, 'e) t
val map : ('a, 'i, 'j, 'd, 'e) t -> f:('a -> 'b) -> ('b, 'i, 'j, 'd, 'e) t
val return : 'a -> ('a, 'i, 'i, 'd, 'e) t
end) (M : sig
type ('a, 'i, 'j, 'd, 'e) t
val to_monad : ('a, 'i, 'j, 'd, 'e) t -> ('a, 'i, 'j, 'd, 'e) Monad.t
val of_monad : ('a, 'i, 'j, 'd, 'e) Monad.t -> ('a, 'i, 'j, 'd, 'e) t
end) =
Make_general (struct
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'i, 'j, 'd, 'e) M.t
let return a = M.of_monad (Monad.return a)
let bind t ~f = M.of_monad (Monad.bind (M.to_monad t) ~f:(fun a -> M.to_monad (f a)))
let map = `Custom (fun t ~f -> M.of_monad (Monad.map (M.to_monad t) ~f))
end)
module Of_monad_indexed
(Monad : S_indexed) (M : sig
type ('a, 'i, 'j) t
val to_monad : ('a, 'i, 'j) t -> ('a, 'i, 'j) Monad.t
val of_monad : ('a, 'i, 'j) Monad.t -> ('a, 'i, 'j) t
end) =
Of_monad_general
(struct
include Monad
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'i, 'j) Monad.t
end)
(struct
include M
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'i, 'j) M.t
end)
module Of_monad3
(Monad : S3) (M : sig
type ('a, 'b, 'c) t
val to_monad : ('a, 'b, 'c) t -> ('a, 'b, 'c) Monad.t
val of_monad : ('a, 'b, 'c) Monad.t -> ('a, 'b, 'c) t
end) =
Of_monad_general
(struct
include Monad
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'd, 'e) Monad.t
end)
(struct
include M
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'd, 'e) M.t
end)
module Of_monad2
(Monad : S2) (M : sig
type ('a, 'b) t
val to_monad : ('a, 'b) t -> ('a, 'b) Monad.t
val of_monad : ('a, 'b) Monad.t -> ('a, 'b) t
end) =
Of_monad_general
(struct
include Monad
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'd) Monad.t
end)
(struct
include M
type ('a, 'i, 'j, 'd, 'e) t = ('a, 'd) M.t
end)
module Of_monad
(Monad : S) (M : sig
type 'a t
val to_monad : 'a t -> 'a Monad.t
val of_monad : 'a Monad.t -> 'a t
end) =
Of_monad_general
(struct
include Monad
type ('a, 'i, 'j, 'd, 'e) t = 'a Monad.t
end)
(struct
include M
type ('a, 'i, 'j, 'd, 'e) t = 'a M.t
end)
module Ident = struct
type 'a t = 'a
include Make (struct
type nonrec 'a t = 'a t
let bind a ~f = f a
let return a = a
let map = `Custom (fun a ~f -> f a)
end)
end