FsToolkit.ErrorHandling.TaskResult 2.13.0

.NET Standard 2.0
There is a newer prerelease version of this package available.
See the version list below for details.
Install-Package FsToolkit.ErrorHandling.TaskResult -Version 2.13.0
dotnet add package FsToolkit.ErrorHandling.TaskResult --version 2.13.0
<PackageReference Include="FsToolkit.ErrorHandling.TaskResult" Version="2.13.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add FsToolkit.ErrorHandling.TaskResult --version 2.13.0
The NuGet Team does not provide support for this client. Please contact its maintainers for support.
#r "nuget: FsToolkit.ErrorHandling.TaskResult, 2.13.0"
#r directive can be used in F# Interactive, C# scripting and .NET Interactive. Copy this into the interactive tool or source code of the script to reference the package.
// Install FsToolkit.ErrorHandling.TaskResult as a Cake Addin
#addin nuget:?package=FsToolkit.ErrorHandling.TaskResult&version=2.13.0

// Install FsToolkit.ErrorHandling.TaskResult as a Cake Tool
#tool nuget:?package=FsToolkit.ErrorHandling.TaskResult&version=2.13.0
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 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
FsToolkit.ErrorHandling.AsyncSeq 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 Versions
.NET net5.0 net5.0-windows net6.0 net6.0-android net6.0-ios net6.0-maccatalyst net6.0-macos net6.0-tvos net6.0-windows
.NET Core netcoreapp2.0 netcoreapp2.1 netcoreapp2.2 netcoreapp3.0 netcoreapp3.1
.NET Standard netstandard2.0 netstandard2.1
.NET Framework net461 net462 net463 net47 net471 net472 net48
MonoAndroid monoandroid
MonoMac monomac
MonoTouch monotouch
Tizen tizen40 tizen60
Xamarin.iOS xamarinios
Xamarin.Mac xamarinmac
Xamarin.TVOS xamarintvos
Xamarin.WatchOS xamarinwatchos
Compatible target framework(s)
Additional computed target framework(s)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (3)

Showing the top 3 NuGet packages that depend on FsToolkit.ErrorHandling.TaskResult:

Package Downloads
NBomber

Modern and flexible load testing framework for Pull and Push scenarios, designed to test any system regardless a protocol (HTTP/WebSockets/AMQP etc) or a semantic model (Pull/Push).

FsToolkit.ErrorHandling.JobResult

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.

FsToolkit.ErrorHandling.IcedTasks

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.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
3.0.0-beta007 2,927 4/15/2022
3.0.0-beta006 82 4/5/2022
3.0.0-beta005 53 4/5/2022
3.0.0-beta004 50 4/5/2022
3.0.0-beta003 132 3/30/2022
3.0.0-beta002 73 2/21/2022
3.0.0-beta001 53 2/21/2022
2.13.0 48,389 1/11/2022
2.13.0-beta001 75 1/11/2022
2.12.0 985 1/6/2022
2.12.0-beta001 70 1/6/2022
2.11.1 9,267 12/1/2021
2.11.1-beta001 659 12/1/2021
2.11.0 3,848 11/24/2021
2.11.0-beta004 3,061 11/24/2021
2.11.0-beta002 2,945 11/24/2021
2.11.0-beta001 2,847 11/24/2021
2.10.0 11,327 11/13/2021
2.9.0 818 11/10/2021
2.9.0-beta001 137 11/10/2021
2.8.1 430 11/7/2021
2.8.0 273 11/7/2021
2.8.0-beta001 210 11/7/2021
2.7.1 1,868 10/19/2021
2.7.1-beta001 179 10/19/2021
2.7.0 11,365 8/2/2021
2.7.0-beta001 177 8/2/2021
2.6.0 2,459 7/7/2021
2.6.0-beta001 170 7/7/2021
2.5.0 7,785 5/26/2021
2.5.0-beta001 169 5/26/2021
2.4.0 542 5/23/2021
2.4.0-beta001 172 5/23/2021
2.3.0 1,575 5/14/2021
2.3.0-beta002 161 5/14/2021
2.2.0 9,363 4/21/2021
2.1.2 19,065 2/27/2021
2.1.1 268 2/26/2021
2.1.1-beta001 162 2/26/2021
2.1.0 322 2/26/2021
2.1.0-beta003 213 2/26/2021
2.1.0-beta002 166 2/25/2021
2.1.0-beta001 164 2/25/2021
2.0.0 197,911 11/20/2020
2.0.0-beta002 288 11/18/2020
2.0.0-beta001 316 8/29/2020
1.4.3 147,115 7/22/2020
1.4.0 2,858 6/5/2020
1.3.2 489 6/5/2020
1.3.1 1,393 5/29/2020
1.3.1-beta001 311 5/25/2020
1.3.0 1,606 5/25/2020
1.3.0-beta006 329 5/25/2020
1.3.0-beta005 356 5/25/2020
1.3.0-beta004 288 5/12/2020
1.2.6 18,555 2/15/2020
1.2.5 11,754 10/18/2019
1.2.4 544 10/10/2019
1.2.3 1,447 7/22/2019
1.2.2 775 5/31/2019
1.2.1 562 5/22/2019
1.1.1 425 5/9/2019
1.1.0 455 5/7/2019

- [Option/ValueOption.ofNull and bindNull](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/164) Credits [@TheAngryByrd](https://github.com/TheAngryByrd)