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module type S = sig
type 'a m
type 'a t
val lift : 'a m -> 'a t
val return : 'a -> 'a t
val fmap : ('a m -> 'b m) -> 'a t -> 'b t
val make : 'a m Seq.t -> 'a m -> 'a t
val bind : 'a t -> ('a m -> 'b t) -> 'b t
val default : 'a t -> 'a m
module Syntax : sig
val ( let* ) : 'a t -> ('a -> 'b m) -> 'b t
val return : 'a -> 'a m
end
end
module Make (M : sig
type 'a t
val bind : 'a t -> ('a -> 'b t) -> 'b t
val return : 'a -> 'a t
end) : S with type 'a m = 'a M.t = struct
type 'a m = 'a M.t
type 'a t = 'a M.t Tree.t
let lift v = Tree.return v
let return v = M.return v |> Tree.return
let bind x f = Tree.bind x f
let fmap f t = bind t (fun gen -> lift @@ f gen)
let make seq root = Tree.of_seq seq root
let default = Tree.root
module Syntax = struct
let ( let* ) (x : 'a t) (f : 'a -> 'b M.t) : 'b t =
fmap (fun gen -> M.bind gen f) x
let return = M.return
end
end