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include Promise_intf
module Make (T : P) : S with type 'a t = 'a T.t = struct
module P = Internal.Promise (T)
module IP = Internal.IndirectPromise
type +'a t = 'a P.t
let t_of_js = P.t_of_js
let t_to_js = P.t_to_js
type error = Ojs.t [@@js]
let make (f : resolve:('a -> unit) -> reject:(error -> unit) -> unit) : 'a t =
let f_safe resolve reject =
let resolve_safe value = resolve (IP.wrap value) in
f ~resolve:resolve_safe ~reject
in
P.new_ f_safe
let resolve (value : 'a) : 'a t = P.resolve (IP.wrap value)
let reject (reason : error) : 'a t = P.reject reason
let catch ~rejected promise = P.catch promise rejected
let then_ ~fulfilled ?rejected promise =
let fulfilled_safe value = fulfilled (IP.unwrap value) in
P.then_ promise ~fulfilled:fulfilled_safe ?rejected ()
let finally ~f promise = P.finally promise f
let all promises =
P.all promises
|> then_ ~fulfilled:(fun arr -> resolve (Array.map IP.unwrap arr))
let all2 promises =
P.all2 promises
|> then_ ~fulfilled:(fun (v1, v2) -> resolve (IP.unwrap v1, IP.unwrap v2))
let all3 promises =
P.all3 promises
|> then_ ~fulfilled:(fun (v1, v2, v3) ->
resolve (IP.unwrap v1, IP.unwrap v2, IP.unwrap v3))
let all_list promises =
all (Array.of_list promises)
|> then_ ~fulfilled:(fun value -> resolve (Array.to_list value))
let race = P.race
let race_list (promises : 'a t list) : 'a t = race (Array.of_list promises)
let return = resolve
let map f promise = then_ ~fulfilled:(fun value -> return (f value)) promise
let bind f promise = then_ ~fulfilled:f promise
module Syntax = struct
let ( >>| ) x f = map f x
let ( >>= ) x f = bind f x
let ( let+ ) x f = map f x
let ( let* ) x f = bind f x
end
module Array = struct
let find_map (f : 'a -> 'b option t) (arr : 'a array) : 'b option t =
let len = Array.length arr in
let rec loop i =
if i = len then
return None
else
let open Syntax in
let* res = f arr.(i) in
match res with
| None -> loop (succ i)
| Some _ as x -> return x
in
loop 0
let filter_map (f : 'a -> 'b option t) (arr : 'a array) : 'b array t =
let open Syntax in
let+ arr = all (Array.map f arr) in
let filter_map = List.filter_map (fun x -> x) in
Array.of_list (filter_map (Array.to_list arr))
end
module List = struct
let rec find_map (f : 'a -> 'b option t) = function
| [] -> return None
| x :: xs -> (
let open Syntax in
let* res = f x in
match res with
| None -> find_map f xs
| Some _ as x -> return x)
let filter_map (f : 'a -> 'b option t) (xs : 'a list) : 'b list t =
let open Syntax in
let+ xs = all_list (List.map f xs) in
List.filter_map (fun x -> x) xs
end
module Option = struct
let iter f =
bind @@ function
| Some x -> return (f x : unit)
| None -> return ()
let map f =
bind @@ function
| Some x -> return (Some (f x))
| None -> return None
let bind f =
bind @@ function
| Some x -> f x
| None -> return None
let return x = return (Some x)
module Syntax = struct
let ( >>| ) x f = map f x
let ( >>= ) x f = bind f x
let ( let+ ) x f = map f x
let ( let* ) x f = bind f x
end
end
module Result = struct
let from_catch promise =
let fulfilled value = return (Ok value) in
let rejected reason = return (Error reason) in
promise |> then_ ~fulfilled ~rejected
let iter ?(ok = ignore) ?(error = ignore) =
bind @@ function
| Ok o -> return (ok o)
| Error e -> return (error e)
let map f =
bind @@ function
| Ok o -> return (Ok (f o))
| Error e -> return (Error e)
let bind f =
bind @@ function
| Ok o -> f o
| Error e -> return (Error e)
let return x = return (Ok x)
module Syntax = struct
let ( >>| ) x f = map f x
let ( >>= ) x f = bind f x
let ( let+ ) x f = map f x
let ( let* ) x f = bind f x
end
end
end
include Make (struct
type +'a t = Ojs.t
let t_of_js _ = Ojs.t_of_js
let t_to_js _ = Ojs.t_to_js
end)