TedToolkit.Results 2026.8.4

TedToolkit.Results

TedToolkit.Results provides immutable result value records for representing an operation as either a success value or an enum failure reason.

Install

dotnet add package TedToolkit.Results

Use

using TedToolkit.Results;

var success = Result.Succeed<string, SaveFailure>("document.json");

if (success)
{
    Console.WriteLine(success.Value);
}

Result<string, SaveFailure> failure = SaveFailure.InvalidDocument;
Console.WriteLine(failure.FailureReason);

enum SaveFailure
{
    InvalidDocument,
}

A result has exactly one active branch. Reading Value from a failed result or FailureReason from a successful result throws InvalidOperationException.

Result<TValue, TFailure> is a readonly value type. Its default value is uninitialized:

Result<string, SaveFailure> result = default;
Console.WriteLine(result.IsInitialized); // false

Reading branch-dependent members or formatting an uninitialized result throws InvalidOperationException.

Consume Branches

Use if (result) for success and if (!result) for failure. These operators have the same branch semantics as IsSuccess and IsFailure; Result is not generally convertible to bool.

if (!result)
{
    Console.WriteLine(result.FailureReason);
}

Install TedToolkit.Results.Composition for Match, TryGetValue, TryGetFailure, deconstruction, and synchronous, Task, or collection pipelines. The core package intentionally keeps these transferable conveniences outside the value contract. JSON and ASP.NET Core adapters are also separate optional packages.

Create Results

Use the non-generic factory when the result type is explicit at the call site:

var success = Result.Succeed<string, SaveFailure>("document.json");
var failure = Result.Fail<string, SaveFailure>(SaveFailure.InvalidDocument);

Constructors and implicit conversions provide equivalent behavior:

Result<string, SaveFailure> success = "document.json";
Result<string, SaveFailure> failure = SaveFailure.InvalidDocument;

Success values may be null when TValue is nullable. TFailure must be an enum value type.

Read Results

• IsInitialized safely identifies whether either branch is active.
• IsSuccess identifies the active branch.
• Value returns the success value.
• FailureReason returns the failure enum.
• An explicit conversion returns the success value and follows the same branch validation as Value.

Result<string, SaveFailure> result = "document.json";
var fileName = (string)result;

Because Result<TValue, TFailure> is a record struct, equality compares the active branch and its contained value.

Diagnostic Text

ToString() prefixes successes with ✅ and failures with ❌:

✅ document.json
❌ InvalidDocument

This text is for logs and debugging only. It is not a serialization, persistence, localization, or user-interface contract.

Internationalization

The package does not hard-code localized presentation text. Source, runtime messages, documentation, and examples use English, while consumer-provided success values remain normal Unicode-capable .NET values. Applications own any locale-specific user-interface text.

Target Frameworks

• net6.0
• net7.0
• net8.0
• net9.0
• net10.0
• net472
• net48
• netstandard2.0
• netstandard2.1

License

Licensed under LGPL-3.0.

Related Documentation

• Repository overview