FsToolkit.ErrorHandling 4.15.1

dotnet add package FsToolkit.ErrorHandling --version 4.15.1
NuGet\Install-Package FsToolkit.ErrorHandling -Version 4.15.1
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="4.15.1" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add FsToolkit.ErrorHandling --version 4.15.1
#r "nuget: FsToolkit.ErrorHandling, 4.15.1"
#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.
// Install FsToolkit.ErrorHandling as a Cake Addin
#addin nuget:?package=FsToolkit.ErrorHandling&version=4.15.1

// Install FsToolkit.ErrorHandling as a Cake Tool
#tool nuget:?package=FsToolkit.ErrorHandling&version=4.15.1

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 Release Prelease
FsToolkit.ErrorHandling NuGet NuGet
FsToolkit.ErrorHandling.TaskResult NuGet NuGet
FsToolkit.ErrorHandling.JobResult NuGet NuGet
FsToolkit.ErrorHandling.AsyncSeq NuGet NuGet
FsToolkit.ErrorHandling.IcedTasks NuGet NuGet

Developing locally

Devcontainer

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

Local Setup

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 exhausting 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)

<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. 
.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)
Additional computed target framework(s)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (26)

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 web clients

FsToolkit.ErrorHandling.AsyncSeq

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

WldMr.Excel.Functions

Generic Excel functions written with ExcelDna and F#. Mostly Array and String related-operations.

Sharpino

Simple F# Event-Sourcing Library

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
4.15.1 9,108 1/15/2024
4.15.0 2,778 1/10/2024
4.14.0 2,648 1/2/2024
4.13.0 4,544 12/10/2023
4.13.0-beta002 734 12/10/2023
4.13.0-beta001 690 12/10/2023
4.12.0 6,182 11/27/2023
4.11.1 2,878 11/23/2023
4.11.0 9,975 11/11/2023
4.10.0 11,247 10/16/2023
4.9.0 157,406 7/10/2023
4.8.0 2,472 7/7/2023
4.7.0 13,407 6/21/2023
4.7.0-beta001 1,211 6/21/2023
4.6.0 51,192 4/20/2023
4.6.0-beta001 1,226 4/20/2023
4.5.0 25,166 3/27/2023
4.5.0-beta002 1,276 3/19/2023
4.5.0-beta001 2,726 3/6/2023
4.4.0 97,292 2/21/2023
4.3.0 49,911 1/20/2023
4.2.1 18,313 12/19/2022
4.2.0 2,100 12/17/2022
4.1.0 8,986 12/13/2022
4.1.0-beta001 1,248 12/13/2022
4.0.0 21,649 11/19/2022
4.0.0-beta001 1,161 11/19/2022
3.3.1 39,872 11/19/2022
3.3.1-beta004 1,245 11/19/2022
3.3.1-beta003 1,214 11/18/2022
3.3.1-beta002 1,249 11/18/2022
3.3.1-beta001 1,166 11/18/2022
3.3.0-beta001 1,209 11/9/2022
3.2.0 112,332 10/31/2022
3.2.0-beta001 1,149 10/31/2022
3.1.0 21,114 10/19/2022
3.0.1 3,122 10/18/2022
3.0.0 7,341 10/14/2022
3.0.0-beta008 1,291 10/14/2022
3.0.0-beta007 28,962 4/15/2022
3.0.0-beta006 1,299 4/5/2022
3.0.0-beta005 1,300 4/5/2022
3.0.0-beta004 1,339 4/5/2022
3.0.0-beta003 1,263 3/30/2022
3.0.0-beta002 1,939 2/21/2022
3.0.0-beta001 1,292 2/21/2022
2.13.0 909,331 1/11/2022
2.13.0-beta001 1,233 1/11/2022
2.12.0 3,577 1/6/2022
2.12.0-beta001 1,235 1/6/2022
2.11.1 32,920 12/1/2021
2.11.1-beta001 1,795 12/1/2021
2.11.0 8,893 11/24/2021
2.11.0-beta004 4,268 11/24/2021
2.11.0-beta002 4,229 11/24/2021
2.11.0-beta001 4,094 11/24/2021
2.10.0 36,193 11/13/2021
2.9.0 7,090 11/10/2021
2.9.0-beta001 1,351 11/10/2021
2.8.1 5,461 11/7/2021
2.8.0 1,832 11/7/2021
2.8.0-beta001 1,467 11/7/2021
2.7.1 9,949 10/19/2021
2.7.1-beta001 1,388 10/19/2021
2.7.0 124,493 8/2/2021
2.7.0-beta001 1,443 8/2/2021
2.6.0 46,537 7/7/2021
2.6.0-beta001 1,415 7/7/2021
2.5.0 58,525 5/26/2021
2.5.0-beta001 1,499 5/26/2021
2.4.0 9,563 5/23/2021
2.4.0-beta001 1,408 5/23/2021
2.3.0 20,730 5/14/2021
2.3.0-beta002 1,335 5/14/2021
2.2.0 14,735 4/21/2021
2.1.2 81,213 2/27/2021
2.1.1 2,406 2/26/2021
2.1.1-beta001 1,426 2/26/2021
2.1.0 1,923 2/26/2021
2.1.0-beta003 1,539 2/26/2021
2.1.0-beta002 1,355 2/25/2021
2.1.0-beta001 1,483 2/25/2021
2.0.0 510,300 11/20/2020
2.0.0-beta002 1,649 11/18/2020
2.0.0-beta001 2,023 8/29/2020
1.4.3 230,691 7/22/2020
1.4.0 8,665 6/5/2020
1.3.2 2,126 6/5/2020
1.3.1 4,096 5/29/2020
1.3.1-beta001 1,692 5/25/2020
1.3.0 4,131 5/25/2020
1.3.0-beta006 1,644 5/25/2020
1.3.0-beta005 1,763 5/25/2020
1.3.0-beta004 1,764 5/12/2020
1.2.6 35,633 2/15/2020
1.2.5 29,031 10/18/2019
1.2.4 2,593 10/10/2019
1.2.3 103,764 7/22/2019
1.2.2 6,369 5/31/2019
1.2.1 27,138 5/22/2019
1.1.1 2,515 5/9/2019
1.1.0 2,198 5/7/2019
1.0.0 4,986 4/10/2019
0.0.14 2,522 1/27/2019
0.0.13 1,198 1/21/2019
0.0.12 1,552 1/4/2019
0.0.11 1,252 1/3/2019
0.0.10 1,229 12/30/2018
0.0.9 1,470 10/5/2018
0.0.8 1,329 10/5/2018
0.0.7 1,340 10/5/2018
0.0.6 1,257 10/4/2018
0.0.5 1,262 9/16/2018
0.0.4 1,297 9/16/2018
0.0.3 1,336 9/8/2018
0.0.2 1,361 9/8/2018
0.0.1 1,516 9/8/2018