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)
Included target framework(s) (in package)
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 10,901 1/15/2024
4.15.0 3,392 1/10/2024
4.14.0 2,906 1/2/2024
4.13.0 4,748 12/10/2023
4.13.0-beta002 805 12/10/2023
4.13.0-beta001 751 12/10/2023
4.12.0 6,477 11/27/2023
4.11.1 3,011 11/23/2023
4.11.0 10,732 11/11/2023
4.10.0 11,588 10/16/2023
4.9.0 164,541 7/10/2023
4.8.0 2,561 7/7/2023
4.7.0 13,616 6/21/2023
4.7.0-beta001 1,291 6/21/2023
4.6.0 52,142 4/20/2023
4.6.0-beta001 1,319 4/20/2023
4.5.0 25,555 3/27/2023
4.5.0-beta002 1,348 3/19/2023
4.5.0-beta001 2,792 3/6/2023
4.4.0 98,929 2/21/2023
4.3.0 50,089 1/20/2023
4.2.1 18,521 12/19/2022
4.2.0 2,167 12/17/2022
4.1.0 9,175 12/13/2022
4.1.0-beta001 1,308 12/13/2022
4.0.0 22,246 11/19/2022
4.0.0-beta001 1,233 11/19/2022
3.3.1 40,504 11/19/2022
3.3.1-beta004 1,324 11/19/2022
3.3.1-beta003 1,294 11/18/2022
3.3.1-beta002 1,336 11/18/2022
3.3.1-beta001 1,235 11/18/2022
3.3.0-beta001 1,250 11/9/2022
3.2.0 112,689 10/31/2022
3.2.0-beta001 1,214 10/31/2022
3.1.0 21,278 10/19/2022
3.0.1 3,215 10/18/2022
3.0.0 7,417 10/14/2022
3.0.0-beta008 1,354 10/14/2022
3.0.0-beta007 29,205 4/15/2022
3.0.0-beta006 1,386 4/5/2022
3.0.0-beta005 1,378 4/5/2022
3.0.0-beta004 1,417 4/5/2022
3.0.0-beta003 1,345 3/30/2022
3.0.0-beta002 2,008 2/21/2022
3.0.0-beta001 1,365 2/21/2022
2.13.0 918,838 1/11/2022
2.13.0-beta001 1,293 1/11/2022
2.12.0 3,642 1/6/2022
2.12.0-beta001 1,314 1/6/2022
2.11.1 33,070 12/1/2021
2.11.1-beta001 1,851 12/1/2021
2.11.0 8,978 11/24/2021
2.11.0-beta004 4,355 11/24/2021
2.11.0-beta002 4,300 11/24/2021
2.11.0-beta001 4,185 11/24/2021
2.10.0 36,315 11/13/2021
2.9.0 7,162 11/10/2021
2.9.0-beta001 1,424 11/10/2021
2.8.1 5,539 11/7/2021
2.8.0 1,913 11/7/2021
2.8.0-beta001 1,540 11/7/2021
2.7.1 10,030 10/19/2021
2.7.1-beta001 1,467 10/19/2021
2.7.0 125,390 8/2/2021
2.7.0-beta001 1,523 8/2/2021
2.6.0 46,611 7/7/2021
2.6.0-beta001 1,468 7/7/2021
2.5.0 58,714 5/26/2021
2.5.0-beta001 1,584 5/26/2021
2.4.0 9,642 5/23/2021
2.4.0-beta001 1,480 5/23/2021
2.3.0 20,812 5/14/2021
2.3.0-beta002 1,400 5/14/2021
2.2.0 14,788 4/21/2021
2.1.2 81,467 2/27/2021
2.1.1 2,518 2/26/2021
2.1.1-beta001 1,513 2/26/2021
2.1.0 1,990 2/26/2021
2.1.0-beta003 1,605 2/26/2021
2.1.0-beta002 1,430 2/25/2021
2.1.0-beta001 1,547 2/25/2021
2.0.0 512,434 11/20/2020
2.0.0-beta002 1,725 11/18/2020
2.0.0-beta001 2,106 8/29/2020
1.4.3 231,245 7/22/2020
1.4.0 8,775 6/5/2020
1.3.2 2,208 6/5/2020
1.3.1 4,187 5/29/2020
1.3.1-beta001 1,767 5/25/2020
1.3.0 4,201 5/25/2020
1.3.0-beta006 1,722 5/25/2020
1.3.0-beta005 1,830 5/25/2020
1.3.0-beta004 1,838 5/12/2020
1.2.6 35,741 2/15/2020
1.2.5 29,149 10/18/2019
1.2.4 2,675 10/10/2019
1.2.3 103,964 7/22/2019
1.2.2 6,441 5/31/2019
1.2.1 27,222 5/22/2019
1.1.1 2,562 5/9/2019
1.1.0 2,280 5/7/2019
1.0.0 5,028 4/10/2019
0.0.14 2,562 1/27/2019
0.0.13 1,238 1/21/2019
0.0.12 1,594 1/4/2019
0.0.11 1,289 1/3/2019
0.0.10 1,269 12/30/2018
0.0.9 1,505 10/5/2018
0.0.8 1,367 10/5/2018
0.0.7 1,378 10/5/2018
0.0.6 1,298 10/4/2018
0.0.5 1,299 9/16/2018
0.0.4 1,337 9/16/2018
0.0.3 1,376 9/8/2018
0.0.2 1,399 9/8/2018
0.0.1 1,553 9/8/2018