package hack_parallel

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Parallel and shared memory library

Install 

dune-project
 Dependency

github.com Readme Edit opam file Versions (3)

Authors

  1. F
    Facebook. Modifications by Rijnard van Tonder

Maintainers

  1. R
    Rijnard van Tonder <rvantonder@gmail.com>

Sources

1.0.1.tar.gz
md5=ba7c72bc207e326b72e294fc76f6ad2c
sha512=5020d47f97bea2f88e2a40411894d03232a7f2282606926c93c7d4c96d72e94a966be852897a9b16f7e0893ba376512045abb9d93020a7c03c3def4f3d918f8e

doc/hack_parallel.hack_core/Hack_result/index.html

Module Hack_resultSource

Result is often used to handle error messages.

Sourcetype ('ok, 'err) t = ('ok, 'err) Pervasives.result =
  1. | Ok of 'ok
  2. | Error of 'err

'a is a function's expected return type, and 'b is often an error message string.

let ric_of_ticker = function
    | "IBM" -> Ok "IBM.N"
    | "MSFT" -> Ok "MSFT.OQ"
    | "AA" -> Ok "AA.N"
    | "CSCO" -> Ok "CSCO.OQ"
    | _ as ticker -> Error (sprintf "can't find ric of %s" ticker)

The return type of ric_of_ticker could be string option, but (string, string) Result.t gives more control over the error message.

include Hack_monad.S2 with type ('a, 'err) t := ('a, 'err) t
include Hack_monad.Infix2 with type ('a, 'err) t := ('a, 'err) t
Sourceval (>>=) : ('a, 'd) t -> ('a -> ('b, 'd) t) -> ('b, 'd) t
Sourceval (>>|) : ('a, 'd) t -> ('a -> 'b) -> ('b, 'd) t
Sourcemodule Monad_infix : Hack_monad.Infix2 with type ('a, 'd) t := ('a, 'd) t
Sourceval bind : ('a, 'd) t -> ('a -> ('b, 'd) t) -> ('b, 'd) t
Sourceval return : 'a -> ('a, _) t
Sourceval join : (('a, 'd) t, 'd) t -> ('a, 'd) t
Sourceval ignore : (_, 'd) t -> (unit, 'd) t
Sourceval all : ('a, 'd) t list -> ('a list, 'd) t
Sourceval all_ignore : (unit, 'd) t list -> (unit, 'd) t
Sourceval fail : 'err -> (_, 'err) t
Sourceval failf : ('a, unit, string, (_, string) t) format4 -> 'a

e.g. failf "Couldn't find bloogle %s" (Bloogle.to_string b)

Sourceval is_ok : (_, _) t -> bool
Sourceval is_error : (_, _) t -> bool
Sourceval ok : ('ok, _) t -> 'ok option
Sourceval error : (_, 'err) t -> 'err option
Sourceval of_option : 'ok option -> error:'err -> ('ok, 'err) t
Sourceval iter : ('ok, _) t -> f:('ok -> unit) -> unit
Sourceval iter_error : (_, 'err) t -> f:('err -> unit) -> unit
Sourceval map : ('ok, 'err) t -> f:('ok -> 'c) -> ('c, 'err) t
Sourceval map_error : ('ok, 'err) t -> f:('err -> 'c) -> ('ok, 'c) t
Sourceval combine : ('ok1, 'err) t -> ('ok2, 'err) t -> ok:('ok1 -> 'ok2 -> 'ok3) -> err:('err -> 'err -> 'err) -> ('ok3, 'err) t
Sourceval ok_fst : ('ok, 'err) t -> [ `Fst of 'ok | `Snd of 'err ]

ok_fst is useful with List.partition_map. Continuing the above example:

  let rics, errors = List.partition_map ~f:Result.ok_fst
      (List.map ~f:ric_of_ticker ["AA"; "F"; "CSCO"; "AAPL"])
Sourceval ok_if_true : bool -> error:'err -> (unit, 'err) t
Sourceval try_with : (unit -> 'a) -> ('a, exn) t
Sourceval ok_exn : ('ok, exn) t -> 'ok

ok_exn t returns x if t = Ok x, and raises exn if t = Error exn

Sourceval ok_or_failwith : ('ok, string) t -> 'ok
Sourceval ok_unit : (unit, _) t

ok_unit = Ok (), used to avoid allocation as a performance hack

Sourcemodule Export : sig ... end
Sourcemodule Stable : sig ... end