Quickstart

Ready to eliminate null checks and stop catching exceptions? Here's how to get up and running with Waystone.Monads.

Installation

Install via the dotnet CLI:

dotnet add package Waystone.Monads

Using Option<T>

The Option<T> type represents a value that may or may not be present. It eliminates the ambiguity and risks of null , and provides a way to mark a value as intentionally absent.

Option<string> name = Option.Some("Liam O'Brian");
Option<string> missing = Option.None<string>();

string greeting = name.Match(
    some => $"Hello, {some}!",
    () => "Hello, stranger!"
);

// Output: "Hello, Liam O'Brian!"

Use Map, Inspect, Match, and more to work with values safely and fluently

Using Result<T, E>

The Result<T, E> type represents a success or failure as a value instead of throwing exceptions. It allows you to reserve exceptions for exceptional scenarios, and provides a framework for handling success and failure outcomes explicitly. Use it instead of throwing exceptions for recoverable failures.

Result<int, string> ParseInt(string input)
{
    return int.TryParse(input, out var value)
        ? Result.Ok<int, string>(value)
        : Result.Err<int, string>($"Input '{input}' is not a valid number");
}

var result = ParseInt("42");

int value = result.Match(
    ok => ok,
    err => -1
);

// Output: 42

No exceptions, no try/catch, just predictable control flow