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module type S = sig
(* avoids a dependency on lwt for sherlodoc.js *)
type 'a t
val return : 'a -> 'a t
val map : 'a t -> ('a -> 'b) -> 'b t
val bind : 'a t -> ('a -> 'b t) -> 'b t
end
module Seq (Io : S) = struct
type 'a t = unit -> 'a node Io.t
and 'a node =
| Nil
| Cons of 'a * 'a t
let rec of_seq s () =
match s () with
| Seq.Nil -> Io.return Nil
| Cons (x, xs) -> Io.return (Cons (x, of_seq xs))
let rec take n xs () =
if n = 0
then Io.return Nil
else begin
Io.map (xs ())
@@ function
| Nil -> Nil
| Cons (x, xs) -> Cons (x, take (n - 1) xs)
end
let rec to_list acc s =
Io.bind (s ())
@@ function
| Nil -> Io.return (List.rev acc)
| Cons (x, xs) -> to_list (x :: acc) xs
let to_list s = to_list [] s
end
|
