# Module Lwt_util

    module Lwt_util: sig .. end

Note: This lodule is deprecated. Use `Lwt_list` and `Lwt_pool` instead.

## Lists iterators

    val iter : ('a -> unit Lwt.t) -> 'a list -> unit Lwt.t

`iter f l` start a thread for each element in `l`. The threads are started according to the list order, but then can run concurrently. It terminates when all the threads are terminated, if all threads are successful. It fails if any of the threads fail.

    val iter_serial : ('a -> unit Lwt.t) -> 'a list -> unit Lwt.t

Similar to `iter` but wait for one thread to terminate before starting the next one.

    val map : ('a -> 'b Lwt.t) -> 'a list -> 'b list Lwt.t

`map f l` apply `f` to each element in `l` and collect the results of the threads thus created. The threads are started according to the list order, but then can run concurrently. `map f l` fails if any of the threads fail.

    val map_with_waiting_action : ('a -> 'b Lwt.t) -> ('a -> unit) -> 'a list -> 'b list Lwt.t

`map_with_waiting_action f wa l` apply `f` to each element in `l` and collect the results of the threads thus created. The threads are started according to the list order, but then can run concurrently. The difference with `map f l` is that function wa will be called on the element that the function is waiting for its termination.

    val map_serial : ('a -> 'b Lwt.t) -> 'a list -> 'b list Lwt.t

Similar to `map` but wait for one thread to terminate before starting the next one.

    val fold_left : ('a -> 'b -> 'a Lwt.t) -> 'a -> 'b list -> 'a Lwt.t

Similar to `List.fold_left`.

## Regions

    type region

    val make_region : int -> region

`make_region sz` create a region of size `sz`.

    val resize_region : region -> int -> unit

`resize_region reg sz` resize the region `reg` to size `sz`.

    val run_in_region : region -> int -> (unit -> 'a Lwt.t) -> 'a Lwt.t

`run_in_region reg size f` execute the thread produced by the function `f` in the region `reg`. The thread is not started before some room is available in the region.