Just.Railway (1.4.1)

2025-07-31T23:53:05+04:00

Setup this registry from the command line:

dotnet nuget add source --name just --username your_username --password your_token

To install the package using NuGet, run the following command:

dotnet add package --source just --version 1.4.1 Just.Railway

For more information on the NuGet registry, see the documentation.

Base for railway-oriented programming in .NET. Package includes Result object, Error class and most of the common extensions.

Base for Railway Programming in .NET

This library uses features of C# to achieve railway-oriented programming.

The desire is to make somewhat user-friendly experience while using result-object pattern.

Features

Immutable Error class
Result object
A bunch of extensions to use result-object pattern with
Try extensions to wrap function calls with result-object
Ensure extensions to utilize result-object in validation scenarios

Getting Started

Install from NuGet.org

# install the package using NuGet
dotnet add package Just.Railway

Examples

Error

using Just.Railway;
Error expectedError = Error.New(type: "Some Error", message: "Some error detail");
Error exceptionalError = Error.New(new Exception("Some Exception"));
Error manyErrors = Error.Many(expectedError, exceptionalError);
// the same result while using .Append(..) or +
manyErrors = expectedError.Append(exceptionalError);
manyErrors = expectedError + exceptionalError;

Note

You can easily serialize/deserialize Error to and from JSON

Result

As return value:

Result Foo()
{
    // ...
    if (SomeCondition())
        return Result.Failure(Error.New("Some Error"));
        // or just: return Error.New("Some Error");
    // ...
    return Result.Success();
}

Result<T> Bar()
{
    T value;
    // ...
    if (SomeCondition())
        return Error.New("Some Error");
    // ...
    return value;
}

Consume Result object

Result<int> result = GetResult();

string value = result
    .Append("new") // -> Result<(int, string)>
    .Map((i, s) => $"{s} result {i}") // -> Result<string>
    .Match(
        onSuccess: x => x,
        onFailure: err => err.ToString()
    );
// value: "new result 1"

Result<int> GetResult() => Result.Success(1);

Recover from failure

Result<string> failed = new NotImplementedException();

Result<string> result = failed.TryRecover(err => err.Type == "System.NotImplementedException"
    ? "recovered"
    : err);
// result with value: "recovered"

Try

Result result = Try.Run(SomeAction);
// you can pass up to 5 arguments like this
result = Try.Run(SomeActionWithArguments, 1, 2.0, "3");

// you also can call functions
Result<int> resultWithValue = Try.Run(SomeFunction);

void SomeAction() {}
void SomeActionWithArguments(int a1, double a2, string? a3) {}
int SomeFunction() => 1;

Ensure

int? value = GetValue();
Result<int> result = Ensure.That(value) // -> Ensure<int?>
    .NotNull() // -> Ensure<int>
    .Satisfies(i => i < 100)
    .Result();

int? GetValue() => 1;

Details

NuGet

just/Just.Railway

2025-07-31 23:53:05 +04:00

1

JustFixMe

Repository Site

586 KiB

Assets (2)

just.railway.1.4.1.nupkg 585 KiB

just.railway.nuspec 1020 B

Versions (7) View all

1.5.0

2025-11-11

1.4.1

2025-07-31

1.4.0

2024-05-18

1.3.0

2024-02-11

1.2.0

2023-12-18

Issues