FsToolkit.ErrorHandling.JobResult 5.0.0-beta011

This is a prerelease version of FsToolkit.ErrorHandling.JobResult.

There is a newer version of this package available.
See the version list below for details.

dotnet add package FsToolkit.ErrorHandling.JobResult --version 5.0.0-beta011

NuGet\Install-Package FsToolkit.ErrorHandling.JobResult -Version 5.0.0-beta011

This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.

<PackageReference Include="FsToolkit.ErrorHandling.JobResult" Version="5.0.0-beta011" />

For projects that support PackageReference, copy this XML node into the project file to reference the package.

<PackageVersion Include="FsToolkit.ErrorHandling.JobResult" Version="5.0.0-beta011" />
                    

                            Directory.Packages.props

<PackageReference Include="FsToolkit.ErrorHandling.JobResult" />
                    

                            Project file

For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package.

paket add FsToolkit.ErrorHandling.JobResult --version 5.0.0-beta011

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

#r "nuget: FsToolkit.ErrorHandling.JobResult, 5.0.0-beta011"

#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.

#addin nuget:?package=FsToolkit.ErrorHandling.JobResult&version=5.0.0-beta011&prerelease
                    

                            Install as a Cake Addin

#tool nuget:?package=FsToolkit.ErrorHandling.JobResult&version=5.0.0-beta011&prerelease
                    

                            Install as a Cake Tool

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

FsToolkit.ErrorHandling

FsToolkit.ErrorHandling is a utility library to work with the Result type in F#, and allows you to do clear, simple and powerful error handling.

The library provides utility functions like map, bind, apply, traverse, sequence as well as computation expressions and infix operators to work with Result<'a, 'b>, Result<'a option, 'b>, Async<Result<'a, 'b>>, Async<Result<'a option, 'b>>, and Result<'a, 'b list>.

It was inspired by Chessie and Cvdm.ErrorHandling (the latter has now been merged into FsToolkit.ErrorHandling).

FsToolkit.ErrorHandling targets .NET Standard 2.0, .NET Standard2.1 and supports Fable.

Documentation

The documentation is available here.

Further material

The main resource as to learning this style of programming Railway Oriented Programming
However Result isn't a panacea, see what pitfalls and where you shouldn't use Result. In defense of Exceptions: Throw (away) your Result

Builds

GitHub Actions

NuGet

Package name	Release	Prelease
FsToolkit.ErrorHandling
FsToolkit.ErrorHandling.TaskResult
FsToolkit.ErrorHandling.JobResult
FsToolkit.ErrorHandling.AsyncSeq
FsToolkit.ErrorHandling.IcedTasks

Developing locally

Devcontainer

This repository has a devcontainer setup for VSCode. For more information see:

VSCode

Local Setup

.NET Core SDK
- v6.x
- v7.x
- v8.x

Optional

To test fable builds locally you will need:

Node
- v18.0.0 or Higher
- Not required but recommend that you use NVM to easily manage multiple versions of Node
Python
- v3.10.0 or higher
- Required for Fable-Python

Compiling

> build.cmd <optional buildtarget> // on windows
$ ./build.sh  <optional buildtarget>// on unix

Without specifying a build target, the default target is DotnetPack, which will run tests for all projects on dotnet and then pack the projects into nuget packages. For additional notable targets see below.

Build Targets

Clean - Will clean all projects bin and obj folders
DotnetTest - Will run tests for dotnet projects
NpmTest - Will run tests for fable-javascript projects
PythonTest - Will run tests for fable-python projects
RunTests - Will run tests for dotnet, fable-javascript and fable-python projects
FormatCode - Will run fantomas to format the codebase

This is not an exhaustive list. Additional targets can be found in the ./build/build.fs file.

A motivating example

This example of composing a login flow shows one example of how this library can aid in clear, simple, and powerful error handling, using just a computation expression and a few helper functions. (The library has many more helper functions and computation expressions as well as infix operators; see the documentation for details.)

// Given the following functions:
//   tryGetUser: string -> Async<User option>
//   isPwdValid: string -> User -> bool
//   authorize: User -> Async<Result<unit, AuthError>>
//   createAuthToken: User -> Result<AuthToken, TokenError>

type LoginError = InvalidUser | InvalidPwd | Unauthorized of AuthError | TokenErr of TokenError

let login (username: string) (password: string) : Async<Result<AuthToken, LoginError>> =
  asyncResult {
    // requireSome unwraps a Some value or gives the specified error if None
    let! user = username |> tryGetUser |> AsyncResult.requireSome InvalidUser

    // requireTrue gives the specified error if false
    do! user |> isPwdValid password |> Result.requireTrue InvalidPwd

    // Error value is wrapped/transformed (Unauthorized has signature AuthError -> LoginError)
    do! user |> authorize |> AsyncResult.mapError Unauthorized

    // Same as above, but synchronous, so we use the built-in mapError
    return! user |> createAuthToken |> Result.mapError TokenErr
  }

Sponsor(s)

Product	Compatible and additional computed target framework versions.
.NET	net5.0 was computed. net5.0-windows was computed. net6.0 was computed. net6.0-android was computed. net6.0-ios was computed. net6.0-maccatalyst was computed. net6.0-macos was computed. net6.0-tvos was computed. net6.0-windows was computed. net7.0 was computed. net7.0-android was computed. net7.0-ios was computed. net7.0-maccatalyst was computed. net7.0-macos was computed. net7.0-tvos was computed. net7.0-windows was computed. net8.0 was computed. net8.0-android was computed. net8.0-browser was computed. net8.0-ios was computed. net8.0-maccatalyst was computed. net8.0-macos was computed. net8.0-tvos was computed. net8.0-windows was computed. net9.0 is compatible. net9.0-android was computed. net9.0-browser was computed. net9.0-ios was computed. net9.0-maccatalyst was computed. net9.0-macos was computed. net9.0-tvos was computed. net9.0-windows was computed. net10.0 was computed. net10.0-android was computed. net10.0-browser was computed. net10.0-ios was computed. net10.0-maccatalyst was computed. net10.0-macos was computed. net10.0-tvos was computed. net10.0-windows was computed.
.NET Core	netcoreapp2.0 was computed. netcoreapp2.1 was computed. netcoreapp2.2 was computed. netcoreapp3.0 was computed. netcoreapp3.1 was computed.
.NET Standard	netstandard2.0 is compatible. netstandard2.1 is compatible.
.NET Framework	net461 was computed. net462 was computed. net463 was computed. net47 was computed. net471 was computed. net472 was computed. net48 was computed. net481 was computed.
MonoAndroid	monoandroid was computed.
MonoMac	monomac was computed.
MonoTouch	monotouch was computed.
Tizen	tizen40 was computed. tizen60 was computed.
Xamarin.iOS	xamarinios was computed.
Xamarin.Mac	xamarinmac was computed.
Xamarin.TVOS	xamarintvos was computed.
Xamarin.WatchOS	xamarinwatchos was computed.

Compatible target framework(s)

Included target framework(s) (in package)

Learn more about Target Frameworks and .NET Standard.

.NETStandard 2.0
- FSharp.Core (>= 6.0.1)
- FsToolkit.ErrorHandling (>= 5.0.0-beta011)
- Hopac (>= 0.5.1)
- Microsoft.Bcl.AsyncInterfaces (>= 6.0.0)
.NETStandard 2.1
- FSharp.Core (>= 6.0.1)
- FsToolkit.ErrorHandling (>= 5.0.0-beta011)
- Hopac (>= 0.5.1)
net9.0
- FSharp.Core (>= 6.0.1)
- FsToolkit.ErrorHandling (>= 5.0.0-beta011)
- Hopac (>= 0.5.1)

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version	Downloads	Last Updated
5.0.0	134	6/2/2025
5.0.0-beta014	129	6/2/2025
5.0.0-beta013	133	5/29/2025
5.0.0-beta012	137	5/1/2025
5.0.0-beta011	139	3/30/2025
5.0.0-beta010	107	3/21/2025
5.0.0-beta009	196	3/5/2025
5.0.0-beta008	101	3/2/2025
5.0.0-beta007	88	2/23/2025
5.0.0-beta006	88	2/21/2025
5.0.0-beta005	92	2/16/2025
5.0.0-beta004	101	2/4/2025
5.0.0-beta003	92	1/6/2025
5.0.0-beta002	94	12/21/2024
5.0.0-beta001	101	12/7/2024
4.18.0	212	10/23/2024
4.18.0-beta001	86	10/23/2024
4.17.0	146	9/23/2024
4.17.0-beta002	84	9/23/2024
4.17.0-beta001	92	9/23/2024
4.16.0	142	7/15/2024
4.15.3	131	7/14/2024
4.15.3-beta001	96	7/14/2024
4.15.2	132	5/2/2024
4.15.2-beta001	82	5/2/2024
4.15.1	221	1/15/2024
4.15.0	157	1/10/2024
4.14.0	157	1/2/2024
4.13.0	195	12/10/2023
4.13.0-beta002	121	12/10/2023
4.13.0-beta001	133	12/10/2023
4.12.0	175	11/27/2023
4.11.1	149	11/23/2023
4.11.0	159	11/11/2023
4.10.0	176	10/16/2023
4.9.0	240	7/10/2023
4.8.0	185	7/7/2023
4.7.0	205	6/21/2023
4.7.0-beta001	141	6/21/2023
4.6.0	237	4/20/2023
4.6.0-beta001	160	4/20/2023
4.5.0	265	3/27/2023
4.5.0-beta002	180	3/19/2023
4.5.0-beta001	162	3/6/2023
4.4.0	323	2/21/2023
4.3.0	358	1/20/2023
4.2.1	350	12/19/2022
4.2.0	381	12/17/2022
4.1.0	321	12/13/2022
4.1.0-beta001	169	12/13/2022
4.0.0	407	11/19/2022
4.0.0-beta001	188	11/19/2022
3.3.1	386	11/19/2022
3.3.1-beta004	170	11/19/2022
3.3.1-beta003	184	11/18/2022
3.3.1-beta002	181	11/18/2022
3.3.1-beta001	178	11/18/2022
3.3.0-beta001	197	11/9/2022
3.2.0	445	10/31/2022
3.2.0-beta001	178	10/31/2022
3.1.0	471	10/19/2022
3.0.1	405	10/18/2022
3.0.0	427	10/14/2022
3.0.0-beta008	191	10/14/2022
3.0.0-beta007	232	4/15/2022
3.0.0-beta006	209	4/5/2022
3.0.0-beta005	204	4/5/2022
3.0.0-beta004	206	4/5/2022
3.0.0-beta003	198	3/30/2022
3.0.0-beta002	208	2/21/2022
3.0.0-beta001	202	2/21/2022
2.13.0	611	1/11/2022
2.13.0-beta001	226	1/11/2022
2.12.0	353	1/6/2022
2.12.0-beta001	221	1/6/2022
2.11.1	998	12/1/2021
2.11.1-beta001	823	12/1/2021
2.11.0	3,370	11/24/2021
2.11.0-beta004	3,260	11/24/2021
2.11.0-beta002	3,156	11/24/2021
2.11.0-beta001	3,047	11/24/2021
2.10.0	407	11/13/2021
2.9.0	402	11/10/2021
2.9.0-beta001	254	11/10/2021
2.8.1	442	11/7/2021
2.8.0	438	11/7/2021
2.8.0-beta001	337	11/7/2021
2.7.1	437	10/19/2021
2.7.1-beta001	295	10/19/2021
2.7.0	595	8/2/2021
2.7.0-beta001	311	8/2/2021
2.6.0	412	7/7/2021
2.6.0-beta001	305	7/7/2021
2.5.0	503	5/26/2021
2.5.0-beta001	282	5/26/2021
2.4.0	441	5/23/2021
2.4.0-beta001	295	5/23/2021
2.3.0	401	5/14/2021
2.3.0-beta002	284	5/14/2021
2.2.0	423	4/21/2021
2.1.2	486	2/27/2021
2.1.1	435	2/26/2021
2.1.1-beta001	289	2/26/2021
2.1.0	505	2/26/2021
2.1.0-beta003	377	2/26/2021
2.1.0-beta002	332	2/25/2021
2.1.0-beta001	323	2/25/2021
2.0.0	833	11/20/2020
2.0.0-beta002	446	11/18/2020
2.0.0-beta001	431	8/29/2020
1.4.3	894	7/22/2020
1.4.0	666	6/5/2020
1.3.2	628	6/5/2020
1.3.1	659	5/29/2020
1.3.1-beta001	474	5/25/2020
1.3.0	675	5/25/2020
1.3.0-beta006	470	5/25/2020
1.3.0-beta005	511	5/25/2020
1.3.0-beta004	459	5/12/2020
1.2.6	725	2/15/2020
1.2.5	740	10/18/2019
1.2.4	662	10/10/2019
1.2.3	768	7/22/2019
1.2.2	741	5/31/2019
1.2.1	750	5/22/2019

- BREAKING: [Remove Ply and update to FSharp 6](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/248) Credits @TheAngryByrd
- BREAKING: [Remove MergeSources (and!) from some implementations like Result](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/261) Credits @TheAngryByrd
- BREAKING: [Merge TaskResult into Core library](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/285) Credits @TheAngryByrd
- This means FsToolkit.ErrorHandling.TaskResult is no longer a separate package and will not be updated. It is now part of the core library.
- BREAKING: [Rename retn to singleton](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/287) Credits @1eyewonder
- BREAKING: [Rename returnError to error + documentation](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/311) Credits @tw0po1nt
- [Use Microsoft.Bcl.AsyncInterfaces in netstandard2.0 (Allows IAsyncDisposable and IAsyncEnumerable)](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/250) Credits @TheAngryByrd
- [Build against Net8](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/251) Credits @TheAngryByrd
- [Fix Overload Resolution to Align to Computation Expression used](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/252) Credits @TheAngryByrd
- [refactor!: Seq.sequenceResultM returns Array instead of seq](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/255) Credits @bartelink
- [feat(Seq): sequenceResultA](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/255) Credits @bartelink
- [Updated uses of Seq.append](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/290) Credits @1eyewonder
- [Add Option.traverseAsync and Option.sequenceAsync](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/298#event-15827853276) Credits @tw0po1nt
- [Add Require and Check helper methods](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/295) Credits @PI-Gorbo
- [Add new AsyncOption APIs and document all its other functions; minor fixes to documentation for Option module](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/307) Credits @tw0po1nt
- [F# 9 support and nullness](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/308) Credits @TheAngryByrd
- [Update IcedTasks 0.11.7](https://github.com/demystifyfp/FsToolkit.ErrorHandling/commit/0a4cc7b3c52efcef47dbc653b00d56ab029bbd01) Credits @TheAngryByrd
- [Add TaskValidation module](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/313) Credits @tw0po1nt
- [feat(Seq.traverse/sequence*)!: Yield arrays](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/310) Credits @bartelink
- [Add ParallelAsync CEs](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/318) Credits @njlr
- [Add Option.sequenceAsyncResult and Option.traverseAsyncResult](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/321) Credits @JayWearsSocks