FsToolkit.ErrorHandling 2.11.0-beta004

This is a prerelease version of FsToolkit.ErrorHandling.
There is a newer version of this package available.
See the version list below for details.
dotnet add package FsToolkit.ErrorHandling --version 2.11.0-beta004
                    
NuGet\Install-Package FsToolkit.ErrorHandling -Version 2.11.0-beta004
                    
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" Version="2.11.0-beta004" />
                    
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageVersion Include="FsToolkit.ErrorHandling" Version="2.11.0-beta004" />
                    
Directory.Packages.props
<PackageReference Include="FsToolkit.ErrorHandling" />
                    
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 --version 2.11.0-beta004
                    
#r "nuget: FsToolkit.ErrorHandling, 2.11.0-beta004"
                    
#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&version=2.11.0-beta004&prerelease
                    
Install FsToolkit.ErrorHandling as a Cake Addin
#tool nuget:?package=FsToolkit.ErrorHandling&version=2.11.0-beta004&prerelease
                    
Install FsToolkit.ErrorHandling as a Cake Tool

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 and .NET Framework 4.6.1 and supports Fable.

Documentation

The documentation is available here.

Further material

Builds

GitHub Actions
GitHub Actions
Build History

NuGet

Package name Badge
FsToolkit.ErrorHandling NuGet
FsToolkit.ErrorHandling.TaskResult NuGet
FsToolkit.ErrorHandling.JobResult NuGet

Developing locally

Requirements
  • .NET Core SDK
    • v3.1.200 or higher
    • Install from here.
  • Node
    • v10.15.0 or LTS
    • Not required but recommend that you use NVM to easily manage multiple versions of Node
Compiling
> build.cmd <optional buildtarget> // on windows
$ ./build.sh  <optional buildtarget>// on unix

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):

<a href="https://www.ajira.tech"><img src="./Ajira-logo.png" alt="Ajira Technologies, India" width="200" /></a>

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 was computed.  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 was computed. 
.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.

NuGet packages (40)

Showing the top 5 NuGet packages that depend on FsToolkit.ErrorHandling:

Package Downloads
FsToolkit.ErrorHandling.TaskResult

FsToolkit.ErrorHandling is an extensive utility library based around the F# Result type, enabling consistent and powerful error handling.

Oryx

.NET SDK for writing HTTP clients

FsToolkit.ErrorHandling.AsyncSeq

FsToolkit.ErrorHandling is an extensive utility library based around the F# Result type, enabling consistent and powerful error handling.

FsToolkit.ErrorHandling.IcedTasks

FsToolkit.ErrorHandling is an extensive utility library based around the F# Result type, enabling consistent and powerful error handling.

FsToolkit.ErrorHandling.JobResult

FsToolkit.ErrorHandling is an extensive utility library based around the F# Result type, enabling consistent and powerful error handling.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
5.0.0-beta012 707 5/1/2025
5.0.0-beta011 396 3/30/2025
5.0.0-beta010 219 3/21/2025
5.0.0-beta009 1,649 3/5/2025
5.0.0-beta008 365 3/2/2025
5.0.0-beta007 974 2/23/2025
5.0.0-beta006 161 2/21/2025
5.0.0-beta005 168 2/16/2025
5.0.0-beta004 345 2/4/2025
5.0.0-beta003 370 1/6/2025
5.0.0-beta002 194 12/21/2024
5.0.0-beta001 2,725 12/7/2024
4.18.0 300,492 10/23/2024
4.18.0-beta001 175 10/23/2024
4.17.0 166,687 9/23/2024
4.17.0-beta002 172 9/23/2024
4.17.0-beta001 164 9/23/2024
4.16.0 80,247 7/15/2024
4.15.3 4,979 7/14/2024
4.15.3-beta001 247 7/14/2024
4.15.2 179,231 5/2/2024
4.15.2-beta001 247 5/2/2024
4.15.1 185,649 1/15/2024
4.15.0 58,247 1/10/2024
4.14.0 5,101 1/2/2024
4.13.0 15,178 12/10/2023
4.13.0-beta002 1,270 12/10/2023
4.13.0-beta001 1,230 12/10/2023
4.12.0 12,464 11/27/2023
4.11.1 4,979 11/23/2023
4.11.0 32,025 11/11/2023
4.10.0 22,889 10/16/2023
4.9.0 526,704 7/10/2023
4.8.0 3,342 7/7/2023
4.7.0 18,051 6/21/2023
4.7.0-beta001 1,746 6/21/2023
4.6.0 111,091 4/20/2023
4.6.0-beta001 1,838 4/20/2023
4.5.0 33,638 3/27/2023
4.5.0-beta002 1,815 3/19/2023
4.5.0-beta001 3,271 3/6/2023
4.4.0 188,123 2/21/2023
4.3.0 54,830 1/20/2023
4.2.1 23,091 12/19/2022
4.2.0 2,673 12/17/2022
4.1.0 10,665 12/13/2022
4.1.0-beta001 1,765 12/13/2022
4.0.0 73,622 11/19/2022
4.0.0-beta001 1,736 11/19/2022
3.3.1 70,308 11/19/2022
3.3.1-beta004 1,847 11/19/2022
3.3.1-beta003 1,733 11/18/2022
3.3.1-beta002 1,803 11/18/2022
3.3.1-beta001 1,720 11/18/2022
3.3.0-beta001 1,754 11/9/2022
3.2.0 133,413 10/31/2022
3.2.0-beta001 1,628 10/31/2022
3.1.0 27,031 10/19/2022
3.0.1 3,669 10/18/2022
3.0.0 8,777 10/14/2022
3.0.0-beta008 1,808 10/14/2022
3.0.0-beta007 33,862 4/15/2022
3.0.0-beta006 1,862 4/5/2022
3.0.0-beta005 1,900 4/5/2022
3.0.0-beta004 1,903 4/5/2022
3.0.0-beta003 1,831 3/30/2022
3.0.0-beta002 2,520 2/21/2022
3.0.0-beta001 1,820 2/21/2022
2.13.0 1,517,522 1/11/2022
2.13.0-beta001 1,791 1/11/2022
2.12.0 4,169 1/6/2022
2.12.0-beta001 1,782 1/6/2022
2.11.1 39,476 12/1/2021
2.11.1-beta001 2,386 12/1/2021
2.11.0 9,502 11/24/2021
2.11.0-beta004 4,853 11/24/2021
2.11.0-beta002 4,759 11/24/2021
2.11.0-beta001 4,695 11/24/2021
2.10.0 37,505 11/13/2021
2.9.0 8,075 11/10/2021
2.9.0-beta001 1,884 11/10/2021
2.8.1 8,419 11/7/2021
2.8.0 2,386 11/7/2021
2.8.0-beta001 2,066 11/7/2021
2.7.1 10,750 10/19/2021
2.7.1-beta001 1,925 10/19/2021
2.7.0 197,774 8/2/2021
2.7.0-beta001 2,034 8/2/2021
2.6.0 49,386 7/7/2021
2.6.0-beta001 2,028 7/7/2021
2.5.0 63,271 5/26/2021
2.5.0-beta001 2,093 5/26/2021
2.4.0 10,185 5/23/2021
2.4.0-beta001 1,974 5/23/2021
2.3.0 21,317 5/14/2021
2.3.0-beta002 1,904 5/14/2021
2.2.0 15,327 4/21/2021
2.1.2 87,966 2/27/2021
2.1.1 3,203 2/26/2021
2.1.1-beta001 2,045 2/26/2021
2.1.0 2,568 2/26/2021
2.1.0-beta003 2,122 2/26/2021
2.1.0-beta002 1,924 2/25/2021
2.1.0-beta001 2,072 2/25/2021
2.0.0 656,075 11/20/2020
2.0.0-beta002 2,300 11/18/2020
2.0.0-beta001 2,705 8/29/2020
1.4.3 263,199 7/22/2020
1.4.0 10,227 6/5/2020
1.3.2 2,791 6/5/2020
1.3.1 4,838 5/29/2020
1.3.1-beta001 2,315 5/25/2020
1.3.0 6,319 5/25/2020
1.3.0-beta006 2,249 5/25/2020
1.3.0-beta005 2,356 5/25/2020
1.3.0-beta004 2,341 5/12/2020
1.2.6 38,840 2/15/2020
1.2.5 30,929 10/18/2019
1.2.4 3,266 10/10/2019
1.2.3 119,838 7/22/2019
1.2.2 7,012 5/31/2019
1.2.1 28,517 5/22/2019
1.1.1 3,163 5/9/2019
1.1.0 2,937 5/7/2019
1.0.0 5,385 4/10/2019
0.0.14 2,881 1/27/2019
0.0.13 1,522 1/21/2019
0.0.12 1,869 1/4/2019
0.0.11 1,603 1/3/2019
0.0.10 1,578 12/30/2018
0.0.9 1,778 10/5/2018
0.0.8 1,677 10/5/2018
0.0.7 1,694 10/5/2018
0.0.6 1,630 10/4/2018
0.0.5 1,609 9/16/2018
0.0.4 1,632 9/16/2018
0.0.3 1,664 9/8/2018
0.0.2 1,661 9/8/2018
0.0.1 2,058 9/8/2018

- [integrates FsToolkit.ErrorHandling.AsyncSeq into main repository] Credits [@njlr](https://github.com/njlr)