This package has been superseded by CSharpFunctionalExtensions.UniTask

Razensoft.Functional

This library helps write code in more functional way. To get to know more about the principles behind it, check out the Applying Functional Principles in C# Pluralsight course.

DISCLAIMER

Most of the code in this library is originating from the awesome CSharpFunctionalExtensions project which you should definitely check out.

Differences between Razensoft.Functional (1.1.0) and CSharpFunctionalExtensions (v2.20.0):

• Removed all classes except Result, UnitResult and Maybe
• Renamed root namespace from CSharpFunctionalExtensions to Razensoft.Functional
• Added extensions methods for UniTask

Installation

There are several ways to install this library into our project:

• Plain install: Clone or download this repository and put it somewhere in your Unity project
• Unity Package Manager (UPM): Add the following line to Packages/manifest.json:
  • "com.razensoft.functional": "https://github.com/Razenpok/Razensoft.Functional.git?path=src/Razensoft.Functional#1.1.0",
• OpenUPM: After installing openupm-cli, run the following command:
  • openupm add com.razensoft.functional

Get rid of primitive obsession

Result<CustomerName> name = CustomerName.Create(model.Name);
Result<Email> email = Email.Create(model.PrimaryEmail);

Result result = Result.Combine(name, email);
if (result.IsFailure)
    return Error(result.Error);

var customer = new Customer(name.Value, email.Value);

Make nulls explicit with the Maybe type

Maybe<Customer> customerOrNothing = _customerRepository.GetById(id);
if (customerOrNothing.HasNoValue)
    return Error("Customer with such Id is not found: " + id);

Compose multiple operations in a single chain

return _customerRepository.GetById(id)
    .ToResult("Customer with such Id is not found: " + id)
    .Ensure(customer => customer.CanBePromoted(), "The customer has the highest status possible")
    .Tap(customer => customer.Promote())
    .Tap(customer => _emailGateway.SendPromotionNotification(customer.PrimaryEmail, customer.Status))
    .Finally(result => result.IsSuccess ? Ok() : Error(result.Error));

Wrap multiple operations in a TransactionScope

return _customerRepository.GetById(id)
    .ToResult("Customer with such Id is not found: " + id)
    .Ensure(customer => customer.CanBePromoted(), "The customer has the highest status possible")
    .WithTransactionScope(customer => Result.Success(customer)
        .Tap(customer => customer.Promote())
        .Tap(customer => customer.ClearAppointments()))
    .Tap(customer => _emailGateway.SendPromotionNotification(customer.PrimaryEmail, customer.Status))
    .Finally(result => result.IsSuccess ? Ok() : Error(result.Error));

Readings and watchings

• Functional C#: Primitive obsession
• Functional C#: Non-nullable reference types
• Functional C#: Handling failures, input errors
• Applying Functional Principles in C# Pluralsight course

Contributors

A big thanks to the project author, Vladimir Khorikov, and to all of the contributors of the original project. Again, don't forget to check it out!