FsToolkit.ErrorHandling
5.0.0-beta002
dotnet add package FsToolkit.ErrorHandling --version 5.0.0-beta002
NuGet\Install-Package FsToolkit.ErrorHandling -Version 5.0.0-beta002
<PackageReference Include="FsToolkit.ErrorHandling" Version="5.0.0-beta002" />
paket add FsToolkit.ErrorHandling --version 5.0.0-beta002
#r "nuget: FsToolkit.ErrorHandling, 5.0.0-beta002"
// Install FsToolkit.ErrorHandling as a Cake Addin #addin nuget:?package=FsToolkit.ErrorHandling&version=5.0.0-beta002&prerelease // Install FsToolkit.ErrorHandling as a Cake Tool #tool nuget:?package=FsToolkit.ErrorHandling&version=5.0.0-beta002&prerelease
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, .NET Standard2.1 and supports Fable.
Documentation
The documentation is available here.
Further material
- The main resource as to learning this style of programming Railway Oriented Programming
- However Result isn't a panacea, see what pitfalls and where you shouldn't use
Result
. In defense of Exceptions: Throw (away) your Result
Builds
GitHub Actions |
---|
NuGet
Package name | Release | Prelease |
---|---|---|
FsToolkit.ErrorHandling | ||
FsToolkit.ErrorHandling.TaskResult | ||
FsToolkit.ErrorHandling.JobResult | ||
FsToolkit.ErrorHandling.AsyncSeq | ||
FsToolkit.ErrorHandling.IcedTasks |
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 projectsbin
andobj
foldersDotnetTest
- Will run tests fordotnet
projectsNpmTest
- Will run tests forfable-javascript
projectsPythonTest
- Will run tests forfable-python
projectsRunTests
- Will run tests fordotnet
,fable-javascript
andfable-python
projectsFormatCode
- Will runfantomas
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 | Versions 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. |
-
.NETStandard 2.0
- FSharp.Core (>= 6.0.1)
- Microsoft.Bcl.AsyncInterfaces (>= 6.0.0)
-
.NETStandard 2.1
- FSharp.Core (>= 6.0.1)
NuGet packages (36)
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.JobResult
FsToolkit.ErrorHandling is an extensive utility library based around the F# Result type, enabling consistent and powerful error handling. |
|
Sharpino
Simple F# Event-Sourcing Library |
GitHub repositories
This package is not used by any popular GitHub repositories.
Version | Downloads | Last updated |
---|---|---|
5.0.0-beta002 | 41 | 12/21/2024 |
5.0.0-beta001 | 412 | 12/7/2024 |
4.18.0 | 32,099 | 10/23/2024 |
4.18.0-beta001 | 165 | 10/23/2024 |
4.17.0 | 64,816 | 9/23/2024 |
4.17.0-beta002 | 164 | 9/23/2024 |
4.17.0-beta001 | 153 | 9/23/2024 |
4.16.0 | 54,376 | 7/15/2024 |
4.15.3 | 3,256 | 7/14/2024 |
4.15.3-beta001 | 238 | 7/14/2024 |
4.15.2 | 127,471 | 5/2/2024 |
4.15.2-beta001 | 220 | 5/2/2024 |
4.15.1 | 153,018 | 1/15/2024 |
4.15.0 | 56,051 | 1/10/2024 |
4.14.0 | 4,920 | 1/2/2024 |
4.13.0 | 12,790 | 12/10/2023 |
4.13.0-beta002 | 1,263 | 12/10/2023 |
4.13.0-beta001 | 1,202 | 12/10/2023 |
4.12.0 | 11,328 | 11/27/2023 |
4.11.1 | 4,572 | 11/23/2023 |
4.11.0 | 29,786 | 11/11/2023 |
4.10.0 | 20,589 | 10/16/2023 |
4.9.0 | 468,018 | 7/10/2023 |
4.8.0 | 3,329 | 7/7/2023 |
4.7.0 | 16,882 | 6/21/2023 |
4.7.0-beta001 | 1,733 | 6/21/2023 |
4.6.0 | 89,969 | 4/20/2023 |
4.6.0-beta001 | 1,819 | 4/20/2023 |
4.5.0 | 33,377 | 3/27/2023 |
4.5.0-beta002 | 1,796 | 3/19/2023 |
4.5.0-beta001 | 3,252 | 3/6/2023 |
4.4.0 | 170,749 | 2/21/2023 |
4.3.0 | 54,040 | 1/20/2023 |
4.2.1 | 22,112 | 12/19/2022 |
4.2.0 | 2,642 | 12/17/2022 |
4.1.0 | 10,627 | 12/13/2022 |
4.1.0-beta001 | 1,742 | 12/13/2022 |
4.0.0 | 53,742 | 11/19/2022 |
4.0.0-beta001 | 1,707 | 11/19/2022 |
3.3.1 | 70,197 | 11/19/2022 |
3.3.1-beta004 | 1,819 | 11/19/2022 |
3.3.1-beta003 | 1,711 | 11/18/2022 |
3.3.1-beta002 | 1,780 | 11/18/2022 |
3.3.1-beta001 | 1,694 | 11/18/2022 |
3.3.0-beta001 | 1,716 | 11/9/2022 |
3.2.0 | 129,064 | 10/31/2022 |
3.2.0-beta001 | 1,599 | 10/31/2022 |
3.1.0 | 25,434 | 10/19/2022 |
3.0.1 | 3,636 | 10/18/2022 |
3.0.0 | 8,335 | 10/14/2022 |
3.0.0-beta008 | 1,782 | 10/14/2022 |
3.0.0-beta007 | 33,045 | 4/15/2022 |
3.0.0-beta006 | 1,825 | 4/5/2022 |
3.0.0-beta005 | 1,858 | 4/5/2022 |
3.0.0-beta004 | 1,871 | 4/5/2022 |
3.0.0-beta003 | 1,791 | 3/30/2022 |
3.0.0-beta002 | 2,482 | 2/21/2022 |
3.0.0-beta001 | 1,783 | 2/21/2022 |
2.13.0 | 1,330,302 | 1/11/2022 |
2.13.0-beta001 | 1,752 | 1/11/2022 |
2.12.0 | 4,128 | 1/6/2022 |
2.12.0-beta001 | 1,742 | 1/6/2022 |
2.11.1 | 38,290 | 12/1/2021 |
2.11.1-beta001 | 2,326 | 12/1/2021 |
2.11.0 | 9,459 | 11/24/2021 |
2.11.0-beta004 | 4,811 | 11/24/2021 |
2.11.0-beta002 | 4,718 | 11/24/2021 |
2.11.0-beta001 | 4,655 | 11/24/2021 |
2.10.0 | 37,405 | 11/13/2021 |
2.9.0 | 8,033 | 11/10/2021 |
2.9.0-beta001 | 1,837 | 11/10/2021 |
2.8.1 | 7,006 | 11/7/2021 |
2.8.0 | 2,346 | 11/7/2021 |
2.8.0-beta001 | 2,026 | 11/7/2021 |
2.7.1 | 10,689 | 10/19/2021 |
2.7.1-beta001 | 1,884 | 10/19/2021 |
2.7.0 | 173,109 | 8/2/2021 |
2.7.0-beta001 | 1,998 | 8/2/2021 |
2.6.0 | 48,585 | 7/7/2021 |
2.6.0-beta001 | 1,990 | 7/7/2021 |
2.5.0 | 62,334 | 5/26/2021 |
2.5.0-beta001 | 2,056 | 5/26/2021 |
2.4.0 | 10,128 | 5/23/2021 |
2.4.0-beta001 | 1,937 | 5/23/2021 |
2.3.0 | 21,279 | 5/14/2021 |
2.3.0-beta002 | 1,870 | 5/14/2021 |
2.2.0 | 15,274 | 4/21/2021 |
2.1.2 | 86,844 | 2/27/2021 |
2.1.1 | 3,157 | 2/26/2021 |
2.1.1-beta001 | 2,001 | 2/26/2021 |
2.1.0 | 2,494 | 2/26/2021 |
2.1.0-beta003 | 2,073 | 2/26/2021 |
2.1.0-beta002 | 1,866 | 2/25/2021 |
2.1.0-beta001 | 2,023 | 2/25/2021 |
2.0.0 | 610,507 | 11/20/2020 |
2.0.0-beta002 | 2,250 | 11/18/2020 |
2.0.0-beta001 | 2,638 | 8/29/2020 |
1.4.3 | 252,148 | 7/22/2020 |
1.4.0 | 9,891 | 6/5/2020 |
1.3.2 | 2,724 | 6/5/2020 |
1.3.1 | 4,782 | 5/29/2020 |
1.3.1-beta001 | 2,266 | 5/25/2020 |
1.3.0 | 5,755 | 5/25/2020 |
1.3.0-beta006 | 2,201 | 5/25/2020 |
1.3.0-beta005 | 2,308 | 5/25/2020 |
1.3.0-beta004 | 2,290 | 5/12/2020 |
1.2.6 | 37,789 | 2/15/2020 |
1.2.5 | 30,552 | 10/18/2019 |
1.2.4 | 3,211 | 10/10/2019 |
1.2.3 | 114,985 | 7/22/2019 |
1.2.2 | 6,932 | 5/31/2019 |
1.2.1 | 28,397 | 5/22/2019 |
1.1.1 | 3,086 | 5/9/2019 |
1.1.0 | 2,816 | 5/7/2019 |
1.0.0 | 5,308 | 4/10/2019 |
0.0.14 | 2,820 | 1/27/2019 |
0.0.13 | 1,462 | 1/21/2019 |
0.0.12 | 1,814 | 1/4/2019 |
0.0.11 | 1,529 | 1/3/2019 |
0.0.10 | 1,481 | 12/30/2018 |
0.0.9 | 1,693 | 10/5/2018 |
0.0.8 | 1,594 | 10/5/2018 |
0.0.7 | 1,611 | 10/5/2018 |
0.0.6 | 1,545 | 10/4/2018 |
0.0.5 | 1,521 | 9/16/2018 |
0.0.4 | 1,547 | 9/16/2018 |
0.0.3 | 1,578 | 9/8/2018 |
0.0.2 | 1,578 | 9/8/2018 |
0.0.1 | 1,890 | 9/8/2018 |
- BREAKING: [Remove Ply and update to FSharp 6](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/248) Credits @TheAngryByrd
- BREAKING: [Remove MergeSources (and!) from some implementations like Result](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/261) Credits @TheAngryByrd
- BREAKING: [Merge TaskResult into Core library](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/285) Credits @TheAngryByrd
- This means FsToolkit.ErrorHandling.TaskResult is no longer a separate package and will not be updated. It is now part of the core library.
- BREAKING: [Rename retn to singleton](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/287) Credits @1eyewonder
- [Use Microsoft.Bcl.AsyncInterfaces in netstandard2.0 (Allows IAsyncDisposable and IAsyncEnumerable)](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/250) Credits @TheAngryByrd
- [Build against Net8](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/251) Credits @TheAngryByrd
- [Fix Overload Resolution to Align to Computation Expression used](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/252) Credits @TheAngryByrd
- [refactor!: Seq.sequenceResultM returns Array instead of seq](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/255) Credits @bartelink
- [feat(Seq): sequenceResultA](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/255) Credits @bartelink
- [Updated uses of Seq.append](https://github.com/demystifyfp/FsToolkit.ErrorHandling/pull/290) Credits @1eyewonder
-