Optional.Async 1.3.0

dotnet add package Optional.Async --version 1.3.0                
NuGet\Install-Package Optional.Async -Version 1.3.0                
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="Optional.Async" Version="1.3.0" />                
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add Optional.Async --version 1.3.0                
#r "nuget: Optional.Async, 1.3.0"                
#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 Optional.Async as a Cake Addin
#addin nuget:?package=Optional.Async&version=1.3.0

// Install Optional.Async as a Cake Tool
#tool nuget:?package=Optional.Async&version=1.3.0                


Async extensions for Nils Luck's Optional library.

It allows you to chain Task<Option<T>> and Task<Option<T, TException>> without having to use await.

Since version 5.0, the Optional library will include its own async extensions. However, at this point they don't provide as much flexibility. To avoid conflicts, the namespace of this library has been changed to Optional.Async.Extensions.

Note: Optional.Async was not meant to be published as a standalone library. It's a collection of extension methods that I had to implement on my own while working with Optional. There are currently no tests and I don't plan on extensively maintaining it. Still, most of the extensions you'll find here are currently being used/have been used for the past year in production code without issues.


Say you have the following asynchronous functions and you want to execute them in order:

Task<Option<User, Error>> CheckIfUserIsAuthorized(string userId, string category);

Task<Option<CloudRecord, Error>> StoreTheFileIntoTheCloud(File file, string category);

Task<Option<Guid, Error>> StoreDatabaseLog(CloudRecord record);

Task<Option<DocumentProcessedResult, Error>> SendToExternalService(Guid key);

Currently, there is no built-in mechanism inside Optional that allows you to chain these calls. What Optional.Async provides is the ability to compose asynchronous functions. The following would be valid syntax:

Task<Option<DocumentProcessedResult, Error>> ProcessDocument(
    string userId,
    string category,
    File file) =>
    CheckIfUserIsAuthorized(userId, category).FlatMapAsync(user =>
    StoreTheFileIntoTheCloud(file, category).FlatMapAsync(cloudRecord =>
    StoreDatabaseLog(cloudRecord).FlatMapAsync(uniqueKey =>

See the DevAdventures RealWorld project and the DDD Café for more examples.

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 was computed. 
.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)
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Learn more about Target Frameworks and .NET Standard.

NuGet packages (2)

Showing the top 2 NuGet packages that depend on Optional.Async:

Package Downloads

Refit based web api client management, but resilient (retry, connectivity, cache, auth, log, priority...)


Provides base commands, queries and handlers.

GitHub repositories (2)

Showing the top 2 popular GitHub repositories that depend on Optional.Async:

Repository Stars
A RealWorld application implemented using the Dev Adventures .NET Core template and functional programming.
Refit based web api client management, but resilient (retry, connectivity, cache, auth, log, priority, etc...)
Version Downloads Last updated
1.3.0 392,712 6/19/2019
1.2.0 3,948 2/8/2019
1.1.0 4,086 11/26/2018
1.0.0 1,932 11/23/2018