MonadicTypes.NET 0.2.0-preview.2

This is a prerelease version of MonadicTypes.NET.

There is a newer prerelease version of this package available.
See the version list below for details.

dotnet add package MonadicTypes.NET --version 0.2.0-preview.2

NuGet\Install-Package MonadicTypes.NET -Version 0.2.0-preview.2

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="MonadicTypes.NET" Version="0.2.0-preview.2" />

For projects that support PackageReference, copy this XML node into the project file to reference the package.

<PackageVersion Include="MonadicTypes.NET" Version="0.2.0-preview.2" />
                    

                            Directory.Packages.props

<PackageReference Include="MonadicTypes.NET" />
                    

                            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 MonadicTypes.NET --version 0.2.0-preview.2

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

#r "nuget: MonadicTypes.NET, 0.2.0-preview.2"

#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 MonadicTypes.NET@0.2.0-preview.2

#: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=MonadicTypes.NET&version=0.2.0-preview.2&prerelease
                    

                            Install as a Cake Addin

#tool nuget:?package=MonadicTypes.NET&version=0.2.0-preview.2&prerelease
                    

                            Install as a Cake Tool

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

MonadicTypes.NET

Allocation-conscious Result<T,E>, Option<T>, Unit, composition, and struct-callable primitives for C# 14 and .NET 10.

Use this core package when expected failure or absence should be represented in the type system without reflection, exceptions for ordinary control flow, or a dependency-injection requirement.

Requirements

.NET 10 or later
Compatible with trimming and NativeAOT
No runtime package dependencies

Install

dotnet add package MonadicTypes.NET --prerelease

Quick Start

using MonadicTypes;

static Result<int, string> ParsePositive(string text) =>
    int.TryParse(text, out int value) && value > 0
        ? Result<int, string>.Ok(value)
        : Result<int, string>.Fail("A positive integer is required.");

string message = ParsePositive("21")
    .Map(static value => value * 2)
    .Match(
        static value => $"Value: {value}",
        static error => $"Error: {error}");

Option<string> name = Option<string>.Some("Ada");
int length = name.Map(static value => value.Length).ValueOr(0);

Core Behavior

Result<T,E> is exactly Ok(T) or Fail(E); its default value is invalid.
Option<T> is Some(T) or None; default(Option<T>) is None.
Equality and hashing inspect only the active Result or Option payload.
Some(null) is rejected.
Map transforms success, Bind composes dependent results, and MapError transforms failure.
Result<Option<T>,E> represents a fallible lookup where absence is expected.
Combine, Zip, and two-through-six-input Map/Bind compose independent results; caller-state forms avoid captured projection delegates.
Option.Traverse exchanges optional input with a fallible stage.
Explicit nullable bridges and deconstruction support application boundaries and patterns.

Normal static callbacks and successful pipelines allocate 0 B in the accepted benchmarks. Caller-state overloads avoid closures, while struct callables are available for measured hot paths. Do not use Result or Option inside parsing or vectorized inner loops where a simpler branch or Try* contract is cheaper.

Package	Add it for
`MonadicTypes.NET.Errors`	Structured errors and validation values
`MonadicTypes.NET.Async`	Fluent Task and ValueTask composition
`MonadicTypes.NET.Effects`	Explicit exception boundaries
`MonadicTypes.NET.Collections`	Count-known fail-fast traversal into arrays
`MonadicTypes.NET.Linq`	Opt-in fluent and query-expression operators
`MonadicTypes.NET.AspNetCore`	Typed HTTP and problem results
`MonadicTypes.NET.Diagnostics`	Optional Activity and Meter projection
`MonadicTypes.NET.Generators`	Compile-time struct-callable adapters

Documentation

See the complete API guide, API behavior reference, and benchmark policy.

Apache-2.0. Developed with AI assistance.

Complete API reference

Documented public members: 141

Product	Compatible and additional computed target framework versions.
.NET	net10.0 is compatible. 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.

Compatible target framework(s)

Included target framework(s) (in package)

Learn more about Target Frameworks and .NET Standard.

net10.0
- No dependencies.

NuGet packages (6)

Showing the top 5 NuGet packages that depend on MonadicTypes.NET:

Package	Downloads
MonadicTypes.NET.Errors Structured, immutable, allocation-conscious errors and validation values for MonadicTypes.NET.	343
MonadicTypes.NET.Async ValueTask- and Task-aware railway operators for MonadicTypes.NET results.	318
MonadicTypes.NET.Effects Explicit exception boundaries and side-effect operators for MonadicTypes.NET pipelines.	265
MonadicTypes.NET.Collections Bounded, allocation-explicit collection traversal for MonadicTypes.NET.	241
MonadicTypes.NET.Linq Opt-in C# query-expression operators for MonadicTypes.NET.	223

GitHub repositories

This package is not used by any popular GitHub repositories.

Version	Downloads	Last Updated
0.3.0-preview.2	49	9/12/2026
0.3.0-preview.1	45	9/12/2026
0.2.0-preview.2	234	8/30/2026
0.2.0-preview.1	119	8/17/2026
0.1.0-preview.1	92	8/12/2026