FsToolkit.ErrorHandling.TaskResult 2.11.1

Install-Package FsToolkit.ErrorHandling.TaskResult -Version 2.11.1
dotnet add package FsToolkit.ErrorHandling.TaskResult --version 2.11.1
<PackageReference Include="FsToolkit.ErrorHandling.TaskResult" Version="2.11.1" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add FsToolkit.ErrorHandling.TaskResult --version 2.11.1
The NuGet Team does not provide support for this client. Please contact its maintainers for support.
#r "nuget: FsToolkit.ErrorHandling.TaskResult, 2.11.1"
#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=2.11.1

// Install FsToolkit.ErrorHandling.TaskResult as a Cake Tool
#tool nuget:?package=FsToolkit.ErrorHandling.TaskResult&version=2.11.1
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>

NuGet packages (2)

Showing the top 2 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.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
2.11.1 22 12/1/2021
2.11.1-beta001 10 12/1/2021
2.11.0 1,140 11/24/2021
2.11.0-beta004 897 11/24/2021
2.11.0-beta002 885 11/24/2021
2.11.0-beta001 865 11/24/2021
2.10.0 781 11/13/2021
2.9.0 467 11/10/2021
2.9.0-beta001 86 11/10/2021
2.8.1 335 11/7/2021
2.8.0 169 11/7/2021
2.8.0-beta001 157 11/7/2021
2.7.1 1,532 10/19/2021
2.7.1-beta001 133 10/19/2021
2.7.0 6,916 8/2/2021
2.7.0-beta001 131 8/2/2021
2.6.0 2,048 7/7/2021
2.6.0-beta001 125 7/7/2021
2.5.0 5,392 5/26/2021
2.5.0-beta001 127 5/26/2021
2.4.0 480 5/23/2021
2.4.0-beta001 135 5/23/2021
2.3.0 1,318 5/14/2021
2.3.0-beta002 116 5/14/2021
2.2.0 6,972 4/21/2021
2.1.2 9,077 2/27/2021
2.1.1 177 2/26/2021
2.1.1-beta001 112 2/26/2021
2.1.0 228 2/26/2021
2.1.0-beta003 163 2/26/2021
2.1.0-beta002 120 2/25/2021
2.1.0-beta001 115 2/25/2021
2.0.0 64,181 11/20/2020
2.0.0-beta002 193 11/18/2020
2.0.0-beta001 259 8/29/2020
1.4.3 97,385 7/22/2020
1.4.0 2,161 6/5/2020
1.3.2 349 6/5/2020
1.3.1 1,249 5/29/2020
1.3.1-beta001 262 5/25/2020
1.3.0 1,458 5/25/2020
1.3.0-beta006 279 5/25/2020
1.3.0-beta005 305 5/25/2020
1.3.0-beta004 224 5/12/2020
1.2.6 16,280 2/15/2020
1.2.5 8,595 10/18/2019
1.2.4 430 10/10/2019
1.2.3 1,322 7/22/2019
1.2.2 637 5/31/2019
1.2.1 422 5/22/2019
1.1.1 334 5/9/2019
1.1.0 345 5/7/2019

- [Seq.sequenceResultM returns seq instead of list](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/159) Credits [@TheAngryByrd](https://github.com/TheAngryByrd)