Book Image

Haskell Cookbook

Book Image

Haskell Cookbook

Overview of this book

Haskell is a purely functional language that has the great ability to develop large and difficult, but easily maintainable software. Haskell Cookbook provides recipes that start by illustrating the principles of functional programming in Haskell, and then gradually build up your expertise in creating industrial-strength programs to accomplish any goal. The book covers topics such as Functors, Applicatives, Monads, and Transformers. You will learn various ways to handle state in your application and explore advanced topics such as Generalized Algebraic Data Types, higher kind types, existential types, and type families. The book will discuss the association of lenses with type classes such as Functor, Foldable, and Traversable to help you manage deep data structures. With the help of the wide selection of examples in this book, you will be able to upgrade your Haskell programming skills and develop scalable software idiomatically.
Table of Contents (13 chapters)

Working with type classes

In this recipe, you will learn about type classes. The type classes provide a common behavior across data types. In this way, a type class abstracts the common behavior and can be implemented by a variety of data. One can relate type classes to interface in C# or C++.

So far, whenever we defined data types we derived the data types from the Show type class without providing any explicit implementation for the type. In such cases, the default implementation is provided by GHC. In this recipe, we will provide explicit implementation for the standard Haskell type classes Show, Read, Enum, Eq, and Ord.

Getting ready

Create a new project called working-with-type-classes using the simple stack template...