Swift 3 Functional Programming

Bring the power of Swift functional programming to iOS, OS X and Web development to build clean, smart and reliable applications

• Written for Swift 3, this is a comprehensive guide that introduces iOS and OS X developers to the all-new world of functional programming that has so far been alien to them
• Learn about first-class functions and how imperative-style patterns can be converted into functional code using some simple techniques
• The book will get you familiar with using functional programming alongside existing OOP techniques so you can get the best of both worlds and develop clean, robust code

The book is for iOS and OS X developers with basic knowledge of Swift programming. Prior knowledge of object-oriented programming is assumed.

• First-class, higher-order, and pure functions
• Closures and capturing values
• Custom operators, recursion, and memoization
• Value and reference types in Swift
• Enumerations, algebraic data types, patterns, and pattern matching
• Generics and associated type protocols
• Higher-order functions such as map, flatMap filter, and reduce
• Dealing with optionals, fmap, and apply for multiple functional mapping
• Functional data structures such as Semigroup, Monoid, Binary Search Tree, Linked List, Stack, and Lazy List
• Immutability, copy constructors, and lenses
• Combining FP paradigms with OOP, FRP, and POP in your day-to-day development activities
• Developing a backend application with Swift
• Developing an iOS application with FP, OOP, FRP, and POP paradigms

Functional programming is getting a lot of attention because it eases many of the difficulties faced in object-oriented programming (OOP) such as testability, maintainability, scalability, and concurrency. Swift has a lot of functional programming features that can be easily used, but most Objective-C and Swift programmers are not familiar with these tools.

This book aims at simplifying the functional programming paradigms and makes it easily usable for Swift programmers, by showing you how to use functional programming paradigms to solve many of your day-to-day development problems. Whether you are new to functional programming and Swift, or experienced, this book will strengthen the skills you need to design and develop high-quality, easily maintainable, scalable, extendable, and efficient applications for iOS, Web, macOS, tvOS, and WatchOS.

The book starts with functional programming concepts, the basics of Swift, and essential concepts such as functions, closures, optionals, enumerations, immutability, and generics in detail with coding examples.

Also, this book introduces more advanced topics such as function composition, functional data structures, monads, functors, applicative functors, memoization, lenses, algebraic data types, functional reactive programming (FRP), protocol-oriented programming (POP), and mixing object-oriented programming (OOP) with functional programming (FP) paradigms.

Finally, this book provides a working code example of a real-world frontend application developed with these techniques and its corresponding backend application developed with Swift.