ZeroAlloc.Results

ZeroAlloc.Results

ZeroAlloc.Results is a zero-allocation, no-boxing Result<T, E> library for .NET 9. All types are readonly struct — no heap allocation, no boxing, no GC pressure.

Install

dotnet add package ZeroAlloc.Results

Quick Example

using ZeroAlloc.Results;
using ZeroAlloc.Results.Extensions;

// Create
Result<int, string> ok = Result<int, string>.Success(42);
Result<int, string> fail = Result<int, string>.Failure("not found");

// Or via implicit conversion
Result<int, string> r = 42;       // success
Result<int, string> e = "error";  // failure

// Chain with Map, Bind, Ensure
var result = GetUser(id)
    .Ensure(u => u.IsActive, "user is inactive")
    .Map(u => u.Email)
    .Bind(email => SendWelcome(email));

// Match to extract
string message = result.Match(
    onSuccess: email => $"Sent to {email}",
    onFailure: err  => $"Failed: {err}");

// LINQ query syntax
var greeting =
    from user    in GetUser(id)
    from profile in GetProfile(user)
    select $"Hello, {profile.Name}";

// Async pipelines with ValueTask
var response = await GetUser(id)
    .MapAsync(async u  => await LoadPermissions(u))
    .BindAsync(async p => await BuildToken(p));

Types

API

Performance

ZeroAlloc.Results is the only result library in .NET with 0 B allocation on every path — including failure construction. .NET 10.0.7, i9-12900HK, BenchmarkDotNet v0.15.4.

On the realistic mixed-success/failure workload, ZeroAlloc.Results is 1.1× faster than OneOf, 42× faster than ErrorOr, and 216× faster than FluentResults — with zero allocation while the latter two allocate per-failure.

Head-to-head vs CSharpFunctionalExtensions: 1.1–8.7× faster depending on operation; 0 B both.

See docs/performance.md for full methodology, all scenarios, and analysis.

Documentation

License

MIT