Functional Extensions for C#
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.
Installation
Available on nuget
PM> Install-Package CSharpFunctionalExtensions
.NET 4.0 version Installation
.NET 4.0 version is available as a separate package on nuget
PM> Install-Package CSharpFunctionalExtensionsNet4.0
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")
.OnSuccess(customer => customer.Promote())
.OnSuccess(customer => _emailGateway.SendPromotionNotification(customer.PrimaryEmail, customer.Status))
.OnBoth(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")
.OnSuccessWithTransactionScope(customer => Result.Ok(customer)
.OnSuccess(customer => customer.Promote())
.OnSuccess(customer => customer.ClearAppointments()))
.OnSuccess(customer => _emailGateway.SendPromotionNotification(customer.PrimaryEmail, customer.Status))
.OnBoth(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 contributors!