Module Lwt_result

Deprecated

Instructions: Use this module in your project

In the IDE (CLion, Visual Studio Code, Xcode, etc.) you use for your DkSDK project:

Add the following to your project's dependencies/CMakeLists.txt:

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DkSDKProject_DeclareAvailable(lwt
    CONSTRAINT "= 5.6.1"
    FINDLIBS lwt lwt.unix)
DkSDKProject_MakeAvailable(lwt)

Add the Findlib::lwt library to any desired targets in src/*/CMakeLists.txt:

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target_link_libraries(YourPackage_YourLibraryName
     # ... existing libraries, if any ...
     Findlib::lwt)

Click your IDE's Build button

Not using DkSDK?

FIRST, do one or all of the following:

Run:
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```
opam install lwt.5.6.1
```

Edit your dune-project and add:

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(package
  (name YourExistingPackage)
  (depends
  ; ... existing dependenices ...
  (lwt (>= 5.6.1))))

Then run:

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dune build *.opam # if this fails, run: dune build

Edit your <package>.opam file and add:

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depends: [
  # ... existing dependencies ...
  "lwt" {>= "5.6.1"}
]

Then run:

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opam install . --deps-only

FINALLY, add the lwt library to any desired (library)and/or (executable) targets in your **/dune files:

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(library
  (name YourLibrary)
  ; ... existing library options ...
  (libraries
    ; ... existing libraries ...
    lwt))

(executable
  (name YourExecutable)
  ; ... existing executable options ...
  (libraries
    ; ... existing libraries ...
    lwt))

This module provides helpers for values of type ('a, 'b) result Lwt.t. The module is experimental and may change in the future.

type ``(+'a, +'b) t`` = ``('a, 'b)`` result Lwt.t

valreturn :'a -> ``('a, _)`` t

valfail :'b -> ``(_, 'b)`` t

val lift : ``('a, 'b)`` result -> ``('a, 'b)`` t

valok :'a Lwt.t -> ``('a, _)`` t

valerror :'b Lwt.t -> ``(_, 'b)`` t

since 5.6.0

valcatch :'a Lwt.t -> ``('a, exn)`` t

catch x behaves like return y if x evaluates to y, and like fail e if x raises e

val get_exn : ``('a, exn)`` t -> 'a Lwt.t

get_exn is the opposite of catch: it unwraps the result type, returning the value in case of success, calls Lwt.fail in case of error.

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

val map_error : ``('e1 -> 'e2)`` -> ``('a, 'e1)`` t -> ``('a, 'e2)`` t

since 5.6.0

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

val bind_error : ``('a, 'e1)`` t -> ``('e1 -> ``('a, 'e2)`` t)`` -> ``('a, 'e2)`` t

since 5.6.0

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

val bind_lwt_error : ``('a, 'e1)`` t -> ``('e1 -> 'e2 Lwt.t)`` -> ``('a, 'e2)`` t

since 5.6.0

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

val both : ``('a, 'e)`` t -> ``('b, 'e)`` t -> ``('a*'b, 'e)`` t

Lwt.both p_1 p_2 returns a promise that is pending until both promises p_1 and p_2 become resolved. If only p_1 is Error e, the promise is resolved with Error e, If only p_2 is Error e, the promise is resolved with Error e, If both p_1 and p_2 resolve with Error _, the promise is resolved with the error that occurred first.

val iter : ``('a ->``unitLwt.t)`` -> ``('a, 'e)`` t ->``unitLwt.t

iter f r is f v if r is a promise resolved with Ok v, and Lwt.return_unit otherwise.

since Lwt 5.6.0

val iter_error : ``('e ->``unitLwt.t)`` -> ``('a, 'e)`` t ->``unitLwt.t

iter_error f r is f v if r is a promise resolved with Error v, and Lwt.return_unit otherwise.

since Lwt 5.6.0

module Infix:sig...end

module Let_syntax:sig...end

module Syntax:sig...end

include module type of Infix

val (>|=) : ``('a, 'e)`` t -> ``('a -> 'b)`` -> ``('b, 'e)`` t

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

Deprecated

val map_err : ``('e1 -> 'e2)`` -> ``('a, 'e1)`` t -> ``('a, 'e2)`` t

deprecated

Alias to map_error since 5.6.0.

val bind_lwt_err : ``('a, 'e1)`` t -> ``('e1 -> 'e2 Lwt.t)`` -> ``('a, 'e2)`` t

deprecated

Alias to bind_lwt_error since 5.6.0.

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