Waystone.Monads.Linq 7.7.0

.NET Standard 2.0 This package targets .NET Standard 2.0. The package is compatible with this framework or higher. 
dotnet add package Waystone.Monads.Linq --version 7.7.0
                    


                    

                
NuGet\Install-Package Waystone.Monads.Linq -Version 7.7.0
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="Waystone.Monads.Linq" Version="7.7.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package. 
<PackageVersion Include="Waystone.Monads.Linq" Version="7.7.0" />
                    


                            Directory.Packages.props
                        

                    

                
<PackageReference Include="Waystone.Monads.Linq" />
                    


                            Project file
For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package. 
paket add Waystone.Monads.Linq --version 7.7.0
                    


                    

                
#r "nuget: Waystone.Monads.Linq, 7.7.0"
#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. 
#:package Waystone.Monads.Linq@7.7.0
#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package. 
#addin nuget:?package=Waystone.Monads.Linq&version=7.7.0
                    


                            Install as a Cake Addin
                        

                    

                
#tool nuget:?package=Waystone.Monads.Linq&version=7.7.0
                    


                            Install as a Cake Tool

Waystone.Monads.Linq

Adds Select, SelectMany and Where to Waystone.Monads, so C# query syntax works over Option and Result.

The core package deliberately does not ship these names. Map, AndThen and Filter are the vocabulary it teaches, and a second spelling of each on the core type would mean every reader learning both. Install this package if you want query syntax; ignore it and nothing changes.

Install

dotnet add package Waystone.Monads.Linq

Then import the namespace wherever you want the names in scope. The using is the opt-in — without it, the operations are still only Map, AndThen and Filter:

using Waystone.Monads.Linq;

Why query syntax

Rust's ? operator early-returns on None or Err, so a multi-step chain reads as straight-line code. C# has no ?, and the method-syntax translation nests one lambda per step. A query expression does not:

Option<Quote> quote =
    from customer in FindCustomer(id)
    from address in customer.PostalAddress
    from rate in RateFor(address)
    select Price(customer, rate);

Every clause after the first is a SelectMany, and each short-circuits: the first None ends the query and no later delegate runs.

The same works over a Result, where the first Err ends the query and is the error that surfaces. Every clause must share one error type — a step that fails differently has to be mapped onto it first.

What maps to what

Query clause This package Core member
select Select Map
second and later from SelectMany AndThen
where Where Filter

Each member is a one-line forward and adds no behaviour, so there is never a reason to prefer one spelling for correctness — only for how the call site reads.

Two things this package does not have

No where clause over a Result. Discarding an ok value would have to invent the error that replaces it, and a signature taking an error factory is not the one query syntax looks for. Filter before entering the query.

No …Async shapes. A query expression cannot await, so an async LINQ name would buy only method-syntax parity with MapAsync, which the core package already provides under the name it actually teaches.

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.  net9.0 was computed.  net9.0-android was computed.  net9.0-browser was computed.  net9.0-ios was computed.  net9.0-maccatalyst was computed.  net9.0-macos was computed.  net9.0-tvos was computed.  net9.0-windows was computed.  net10.0 was computed.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-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)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last Updated
7.7.0 37 10/5/2026
7.6.0 35 10/5/2026
7.5.0 80 9/30/2026
7.4.0 98 9/15/2026
7.3.0 96 9/13/2026
7.2.0 95 9/9/2026
7.1.0 106 9/4/2026
7.1.0-beta.2 64 9/3/2026
7.1.0-beta.1 74 9/2/2026
7.0.1 97 8/30/2026
7.0.0 95 8/30/2026
7.0.0-beta.3 65 8/29/2026
7.0.0-beta.2 71 8/27/2026

https://github.com/draekien-industries/waystone-dotnet/releases