Mastering Javascript Functional Programming

Explore the functional programming paradigm and the different techniques for developing better algorithms, writing more concise code, and performing seamless testing Key FeaturesExplore this second edition updated to cover features like async functions and transducers, as well as functional reactive programmingEnhance your functional programming (FP) skills to build web and server apps using JavaScriptUse FP to enhance the modularity, reusability, and performance of appsBook Description Functional programming is a paradigm for developing software with better performance. It helps you write concise and testable code. To help you take your programming skills to the next level, this comprehensive book will assist you in harnessing the capabilities of functional programming with JavaScript and writing highly maintainable and testable web and server apps using functional JavaScript. This second edition is updated and improved to cover features such as transducers, lenses, prisms and various other concepts to help you write efficient programs. By focusing on functional programming, you’ll not only start to write but also to test pure functions, and reduce side effects. The book also specifically allows you to discover techniques for simplifying code and applying recursion for loopless coding. Gradually, you’ll understand how to achieve immutability, implement design patterns, and work with data types for your application, before going on to learn functional reactive programming to handle complex events in your app. Finally, the book will take you through the design patterns that are relevant to functional programming. By the end of this book, you’ll have developed your JavaScript skills and have gained knowledge of the essential functional programming techniques to program effectively. What you will learnSimplify JavaScript coding using function composition, pipelining, chaining, and transducingUse declarative coding as opposed to imperative coding to write clean JavaScript codeCreate more reliable code with closures and immutable dataApply practical solutions to complex programming problems using recursionImprove your functional code using data types, type checking, and immutabilityUnderstand advanced functional programming concepts such as lenses and prisms for data accessWho this book is for This book is for JavaScript developers who want to enhance their programming skills and build efficient web applications. Frontend and backend developers who use various JavaScript frameworks and libraries like React, Angular, or Node.js will also find the book helpful. Working knowledge of ES2019 is required to grasp the concepts covered in the book easily.

Master Functional Programming techniques with this comprehensive guide for writing cleaner, safer, high-performing JavaScript codes About This Book Become proficient and skilled with Functional Programming in JavaScript to solve real-world development problems Successfully apply Functional Programming concepts and techniques to everyday JavaScript programming Bring modularity, reusability, testability, and performance to your web apps Who This Book Is For If you are a JavaScript developer and want to apply functional programming techniques, then this book is for you. Only a basic knowledge of the concepts of functional programming is required for this book. What You Will Learn Create more reliable code with closures and immutable data Convert existing methods into pure functions, and loops into recursive methods Develop more powerful applications with currying and function composition Separate the logic of your system from implementation details Implement composition and chaining techniques to simplify coding Use functional programming techniques where it makes the most sense In Detail Functional programming is a programming paradigm for developing software using functions. Learning to use functional programming is a good way to write more concise code, with greater concurrency and performance. The JavaScript language is particularly suited to functional programming. This book provides comprehensive coverage of the major topics in functional programming with JavaScript to produce shorter, clearer, and testable programs. You'll delve into functional programming; including writing and testing pure functions, reducing side-effects, and other features to make your applications functional in nature. Specifically, we'll explore techniques to simplify coding, apply recursion for loopless coding, learn ways to achieve immutability, implement design patterns, and work with data types. By the end of this book, you'll have developed the JavaScript skills you need to program functional applications with confidence. Style and approach This book takes an easy-to-follow, step-by-step tutorial approach. You will make the most of JavaScript programming with a focus on the progression of functional programming techniques, styles, and detailed information about JavaScript libraries.

Apply functional programming techniques to write testable terser code for frontend and backend development with improved clarity, concurrency, and performance Purchase of the print or Kindle book includes a free PDF eBook Key Features Apply functional programming concepts and techniques to everyday JavaScript or TypeScript programming Master functional programming in JavaScript and TypeScript to solve real-world development problems Apply functional programming to get better testable programs with higher modularity and reusability Book Description Functional programming is a programming paradigm that uses functions for developing software. This book is filled with examples that enable you to leverage the latest JavaScript and TypeScript versions to produce modern and clean code, as well as teach you to how apply functional programming techniques to develop more efficient algorithms, write more concise code, and simplify unit testing. This book provides comprehensive coverage of the major topics in functional programming to produce shorter, clearer, and testable programs. You'll begin by getting to grips with writing and testing pure functions, reducing side effects, as well as other key features to make your applications functional in nature. The book specifically explores techniques to simplify coding, apply recursion, perform high-level coding, learn ways to achieve immutability, implement design patterns, and work with data types. By the end of this book, you'll have developed the practical programming skills needed to confidently enhance your applications by adding functional programming to wherever it's most suitable. What you will learn Understand when to use functional programming versus classic object-oriented programming Use declarative coding instead of imperative coding for clearer, more understandable code Know how to avoid side effects and create more reliable code with closures and immutable data Use recursion to help design and implement more understandable solutions to complex problems Define functional programing data types with or without TypeScript, add type checking, and implement immutability Apply advanced containers to get better structures to tackle errors and implement async programming Who this book is for If you are a JavaScript or TypeScript developer looking to enhance your programming skills, then this book is for you. The book applies to both frontend developers working with frameworks such as React, Vue, or Angular as well as backend developers using Node.js or Deno.

Learn how functional programming can help you in deploying web servers and working with databases in a declarative and pure way Key Features Learn functional programming from scratch Program applications with side effects in a pure way Gain expertise in working with array tools for functional programming Book Description In large projects, it can get difficult keeping track of all the interdependencies of the code base and how its state changes at runtime. Functional Programming helps us solve these problems. It is a paradigm specifically designed to deal with the complexity of software development. This book will show you how the right abstractions can reduce complexity and make your code easy to read and understand. Mastering Functional Programming begins by touching upon the basics such as what lambdas are and how to write declarative code with the help of functions. It then moves on to more advanced concepts such as pure functions and type classes, the problems they aim to solve, and how to use them in real-world scenarios. You will also explore some of the more advanced patterns in the world of functional programming, such as monad transformers and Tagless Final. In the concluding chapters, you will be introduced to the actor model, implement it in modern functional languages, and explore the subject of parallel programming. By the end of the book, you will have mastered the concepts entailing functional programming along with object-oriented programming (OOP) to build robust applications. What you will learn Write reliable and scalable software based on solid foundations Explore the cutting edge of computer science research Effectively solve complex architectural problems in a robust way Avoid unwanted outcomes such as errors or delays and focus on business logic Write parallel programs in a functional style using the actor model Use functional data structures and collections in your day-to-day work Who this book is for If you are from an imperative and OOP background, this book will guide you through the world of functional programming, irrespective of which programming language you use.

Write reliable code to create powerful applications by mastering advanced JavaScript design patterns About This Book Learn how to use tried and true software design methodologies to enhance your JavaScript code Discover robust JavaScript implementations of classic and advanced design patterns Packed with easy-to-follow examples that can be used to create reusable code and extensible designs Who This Book Is For This book is ideal for JavaScript developers who want to gain expertise in object-oriented programming with JavaScript and the new capabilities of ES-2015 to improve their web development skills and build professional-quality web applications. What You Will Learn Harness the power of patterns for tasks ranging from application building to code testing Rethink and revitalize your code with the use of functional patterns Improve the way you organize your code Build large-scale apps seamlessly with the help of reactive patterns Identify the best use cases for microservices Get to grips with creational, behavioral, and structural design patterns Explore advanced design patterns including dependency injection In Detail With the recent release of ES-2015, there are several new object-oriented features and functions introduced in JavaScript. These new features enhance the capabilities of JavaScript to utilize design patterns and software design methodologies to write powerful code. Through this book, you will explore how design patterns can help you improve and organize your JavaScript code. You'll get to grips with creational, structural and behavioral patterns as you discover how to put them to work in different scenarios. Then, you'll get a deeper look at patterns used in functional programming, as well as model view patterns and patterns to build web applications. This updated edition will also delve into reactive design patterns and microservices as they are a growing phenomenon in the world of web development. You will also find patterns to improve the testability of your code using mock objects, mocking frameworks, and monkey patching. We'll also show you some advanced patterns including dependency injection and live post processing. By the end of the book, you'll be saved of a lot of trial and error and developmental headaches, and you will be on the road to becoming a JavaScript expert. Style and approach Packed with several real-world use cases, this book shows you through step-by-step instructions how to implement the advanced object-oriented programming features to build sophisticated web applications that promote scalability and reusability.

How can you overcome JavaScript language oddities and unsafe features? With this book, you’ll learn how to create code that’s beautiful, safe, and simple to understand and test by using JavaScript’s functional programming support. Author Michael Fogus shows you how to apply functional-style concepts with Underscore.js, a JavaScript library that facilitates functional programming techniques. Sample code is available on GitHub at https://github.com/funjs/book-source. Fogus helps you think in a functional way to help you minimize complexity in the programs you build. If you’re a JavaScript programmer hoping to learn functional programming techniques, or a functional programmer looking to learn JavaScript, this book is the ideal introduction. Use applicative programming techniques with first-class functions Understand how and why you might leverage variable scoping and closures Delve into higher-order functions—and learn how they take other functions as arguments for maximum advantage Explore ways to compose new functions from existing functions Get around JavaScript’s limitations for using recursive functions Reduce, hide, or eliminate the footprint of state change in your programs Practice flow-based programming with chains and functional pipelines Discover how to code without using classes

Expand your boundaries by creating applications empowered with real-time data using RxJs without compromising performance About This Book Handle an infinite stream of incoming data using RxJs without going crazy Explore important RxJs operators that can help you improve your code readability Get acquainted with the different techniques and operators used to handle data traffic, which occurs when you receive data faster than you can process Who This Book Is For If you're a web developer with some basic JavaScript programming knowledge who wants to implement the reactive programming paradigm with JavaScript, then this book is for you. What You Will Learn Get to know the basics of functional reactive programming using RxJs Process a continuous flow of data with linear memory consumption Filter, group, and react to changes in your system Discover how to deal with data traffic Compose operators to create new operators and use them in multiple observables to avoid code repetition Explore transducers and see how they can improve your code readability Detect and recover from errors in observables using Retry and Catch operators Create your own reactive application: a real-time webchat In Detail If you're struggling to handle a large amount of data and don't know how to improve your code readability, then reactive programming is the right solution for you. It lets you describe how your code behaves when changes happen and makes it easier to deal with real-time data. This book will teach you what reactive programming is, and how you can use it to write better applications. The book starts with the basics of reactive programming, what Reactive Extensions is, and how can you use it in JavaScript along with some reactive code using Bacon. Next, you'll discover what an Observable and an Observer are and when to use them.You'll also find out how you can query data through operators, and how to use schedulers to react to changes. Moving on, you'll explore the RxJs API, be introduced to the problem of data traffic (backpressure), and see how you can mitigate it. You'll also learn about other important operators that can help improve your code readability, and you'll see how to use transducers to compose operators. At the end of the book, you'll get hands-on experience of using RxJs, and will create a real-time web chat using RxJs on the client and server, providing you with the complete package to master RxJs. Style and approach This easy-to-follow guide is full of hands-on examples of reactive programming. Each topic is explained and placed in context, and for the more inquisitive there are more details of the concepts used, ending with an application using the concepts learned through the book.

Summary Functional Programming in JavaScript teaches JavaScript developers functional techniques that will improve extensibility, modularity, reusability, testability, and performance. Through concrete examples and jargon-free explanations, this book teaches you how to apply functional programming to real-life development tasks Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology In complex web applications, the low-level details of your JavaScript code can obscure the workings of the system as a whole. As a coding style, functional programming (FP) promotes loosely coupled relationships among the components of your application, making the big picture easier to design, communicate, and maintain. About the Book Functional Programming in JavaScript teaches you techniques to improve your web applications - their extensibility, modularity, reusability, and testability, as well as their performance. This easy-to-read book uses concrete examples and clear explanations to show you how to use functional programming in real life. If you're new to functional programming, you'll appreciate this guide's many insightful comparisons to imperative or object-oriented programming that help you understand functional design. By the end, you'll think about application design in a fresh new way, and you may even grow to appreciate monads! What's Inside High-value FP techniques for real-world uses Using FP where it makes the most sense Separating the logic of your system from implementation details FP-style error handling, testing, and debugging All code samples use JavaScript ES6 (ES 2015) About the Reader Written for developers with a solid grasp of JavaScript fundamentals and web application design. About the Author Luis Atencio is a software engineer and architect building enterprise applications in Java, PHP, and JavaScript. Table of Contents PART 1 THINK FUNCTIONALLY Becoming functional Higher-order JavaScript PART 2 GET FUNCTIONAL Few data structures, many operations Toward modular, reusable code Design patterns against complexity PART 3 ENHANCING YOUR FUNCTIONAL SKILLS Bulletproofing your code Functional optimizations Managing asynchronous events and data