Source file seq_es.ml

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(** The [S] signature is similar to {!Seq.S} except that suspended nodes are
    wrapped in a result-Lwt.

    This allows some additional traversors ([map_ep], etc.) to be applied
    lazily.

    The functions [of_seq] and [of_seq_*] allow conversion from vanilla
    sequences. *)
module type S = sig
  type ('a, 'e) seq_e_t (* For substitution by [Seq_e.t] *)

  type 'a seq_s_t (* For substitution by [Seq_s.t] *)

  (** This is similar to {!Seq.S}[.t] but the suspended node is a promised
      result.

      Similarly to [Seq_e], sequences of this module can be interrupted by an
      error. In this case, traversal has fully applied to the successful prefix
      before the returned promise evaluates to [Error _].
   *)
  type (+'a, 'e) node = Nil | Cons of 'a * ('a, 'e) t

  and ('a, 'e) t = unit -> (('a, 'e) node, 'e) result Lwt.t

  val empty : ('a, 'e) t

  val nil : ('a, 'e) node

  val cons : 'a -> ('a, 'e) t -> ('a, 'e) t

  val cons_s : 'a Lwt.t -> ('a, 'e) t -> ('a, 'e) t

  val cons_e : ('a, 'e) result -> ('a, 'e) t -> ('a, 'e) t

  val cons_es : ('a, 'e) result Lwt.t -> ('a, 'e) t -> ('a, 'e) t

  val append : ('a, 'e) t -> ('a, 'e) t -> ('a, 'e) t

  val return : 'a -> ('a, 'e) t

  val return_e : ('a, 'e) result -> ('a, 'e) t

  val return_s : 'a Lwt.t -> ('a, 'e) t

  val return_es : ('a, 'e) result Lwt.t -> ('a, 'e) t

  val interrupted : 'e -> ('a, 'e) t

  val interrupted_s : 'e Lwt.t -> ('a, 'e) t

  val first : ('a, 'e) t -> ('a, 'e) result option Lwt.t

  val fold_left : ('a -> 'b -> 'a) -> 'a -> ('b, 'e) t -> ('a, 'e) result Lwt.t

  (** See {!Seq_e.fold_left_e} for a warning about traversal and interruption
      errors being indistinguishable. This applies to all [_e] and [_es]
      functions of this module. *)
  val fold_left_e :
    ('a -> 'b -> ('a, 'e) result) -> 'a -> ('b, 'e) t -> ('a, 'e) result Lwt.t

  val fold_left_s :
    ('a -> 'b -> 'a Lwt.t) -> 'a -> ('b, 'e) t -> ('a, 'e) result Lwt.t

  val fold_left_es :
    ('a -> 'b -> ('a, 'e) result Lwt.t) ->
    'a ->
    ('b, 'e) t ->
    ('a, 'e) result Lwt.t

  val iter : ('a -> unit) -> ('a, 'e) t -> (unit, 'e) result Lwt.t

  val iter_e :
    ('a -> (unit, 'e) result) -> ('a, 'e) t -> (unit, 'e) result Lwt.t

  val iter_s : ('a -> unit Lwt.t) -> ('a, 'e) t -> (unit, 'e) result Lwt.t

  val iter_es :
    ('a -> (unit, 'e) result Lwt.t) -> ('a, 'e) t -> (unit, 'e) result Lwt.t

  val map : ('a -> 'b) -> ('a, 'e) t -> ('b, 'e) t

  val map_e : ('a -> ('b, 'e) result) -> ('a, 'e) t -> ('b, 'e) t

  val map_s : ('a -> 'b Lwt.t) -> ('a, 'e) t -> ('b, 'e) t

  val map_es : ('a -> ('b, 'e) result Lwt.t) -> ('a, 'e) t -> ('b, 'e) t

  val map_error : ('e -> 'f) -> ('a, 'e) t -> ('a, 'f) t

  val map_error_s : ('e -> 'f Lwt.t) -> ('a, 'e) t -> ('a, 'f) t

  val filter : ('a -> bool) -> ('a, 'e) t -> ('a, 'e) t

  val filter_e : ('a -> (bool, 'e) result) -> ('a, 'e) t -> ('a, 'e) t

  val filter_s : ('a -> bool Lwt.t) -> ('a, 'e) t -> ('a, 'e) t

  val filter_es : ('a -> (bool, 'e) result Lwt.t) -> ('a, 'e) t -> ('a, 'e) t

  val filter_map : ('a -> 'b option) -> ('a, 'e) t -> ('b, 'e) t

  val filter_map_e : ('a -> ('b option, 'e) result) -> ('a, 'e) t -> ('b, 'e) t

  val filter_map_s : ('a -> 'b option Lwt.t) -> ('a, 'e) t -> ('b, 'e) t

  val filter_map_es :
    ('a -> ('b option, 'e) result Lwt.t) -> ('a, 'e) t -> ('b, 'e) t

  val unfold : ('b -> ('a * 'b) option) -> 'b -> ('a, 'e) t

  val unfold_s : ('b -> ('a * 'b) option Lwt.t) -> 'b -> ('a, 'e) t

  val unfold_e : ('b -> (('a * 'b) option, 'e) result) -> 'b -> ('a, 'e) t

  val unfold_es :
    ('b -> (('a * 'b) option, 'e) result Lwt.t) -> 'b -> ('a, 'e) t

  val of_seq : 'a Stdlib.Seq.t -> ('a, 'e) t

  val of_seq_s : 'a Lwt.t Stdlib.Seq.t -> ('a, 'e) t

  val of_seqs : 'a seq_s_t -> ('a, 'e) t

  val of_seq_e : ('a, 'e) result Stdlib.Seq.t -> ('a, 'e) t

  val of_seqe : ('a, 'e) seq_e_t -> ('a, 'e) t

  val of_seq_es : ('a, 'e) result Lwt.t Stdlib.Seq.t -> ('a, 'e) t
end