Modern Asynchronous JavaScript

Author: Faraz K. Kelhini
Publisher: Pragmatic Bookshelf
ISBN: 1680509276
Category : Computers
Languages : en
Pages : 114

Book Description
JavaScript today must interact with data-intensive APIs and networks. The solution is a program that can work asynchronously instead of finishing tasks in order. In modern JavaScript, instead of callbacks you'll use promises to improve your application's performance and responsiveness. JavaScript features introduced in ES2020, ES2021, and ESNext like Promise.allSettled(), Promise.any(), and top-level await help you develop small, fast, low-profile applications. With the AbortController API, cancel a pending async request before it has completed. Modern Asynchronous JavaScript gives you an arsenal of tools to build programs that always respond to user requests, recover quickly from difficult conditions, and deliver maximum performance. Applications today must work with information on remote servers, and users expect a quick response to complex interactions at all times, whether on a high-speed 5G cellular network or slow public WiFi. JavaScript provides developers with advanced tools to coordinate the asynchronous parts of their code efficiently and deliver responsive programs. Faster applications equal happier users, which is the promise of asynchronous JavaScript. With Modern Asynchronous JavaScript you'll learn techniques for managing your async code. Features like ES2021 Promise.any() allow you to safeguard your async code from external issues that are out of your control like server downtime. You'll discover secret weapons like top-level await to initialize resources, define dependency paths dynamically, and load dependencies with a fallback implementation. You'll even learn to how to set a time limit for async requests and react if they take too long to complete. Fast, reliable applications are a must in today's world, where users demand increasingly greater amounts of data on mobile devices. Asynchronous programming may require more cautious planning than synchronous programming but the outcome is rewarding. Asynchronous JavaScript allows you to write code that is nimble but reliable, leading to programs that load faster, respond quicker, and most importantly that you can trust to function properly. What You Need: You'll need an intermediate level of JavaScript programming skills and a browser that supports features from ES2020, ES2021, and ESNext.

Async JavaScript

Author: Trevor Burnham
Publisher: Pragmatic Bookshelf
ISBN: 168050312X
Category : Computers
Languages : en
Pages : 144

Book Description
With the advent of HTML5, front-end MVC, and Node.js, JavaScript is ubiquitous--and still messy. This book will give you a solid foundation for managing async tasks without losing your sanity in a tangle of callbacks. It's a fast-paced guide to the most essential techniques for dealing with async behavior, including PubSub, evented models, and Promises. With these tricks up your sleeve, you'll be better prepared to manage the complexity of large web apps and deliver responsive code. With Async JavaScript, you'll develop a deeper understanding of the JavaScript language. You'll start with a ground-up primer on the JavaScript event model--key to avoiding many of the most common mistakes JavaScripters make. From there you'll see tools and design patterns for turning that conceptual understanding into practical code. The concepts in the book are illustrated with runnable examples drawn from both the browser and the Node.js server framework, incorporating complementary libraries including jQuery, Backbone.js, and Async.js. You'll learn how to create dynamic web pages and highly concurrent servers by mastering the art of distributing events to where they need to be handled, rather than nesting callbacks within callbacks within callbacks. Async JavaScript will get you up and running with real web development quickly. By the time you've finished the Promises chapter, you'll be parallelizing Ajax requests or running animations in sequence. By the end of the book, you'll even know how to leverage Web Workers and AMD for JavaScript applications with cutting-edge performance. Most importantly, you'll have the knowledge you need to write async code with confidence. What You Need: Basic knowledge of JavaScript is recommended. If you feel that you're not up to speed, see the "Resources for Learning JavaScript" section in the preface.

JavaScript with Promises

Author: Daniel Parker
Publisher: "O'Reilly Media, Inc."
ISBN: 1491930748
Category : Computers
Languages : en
Pages : 130

Book Description
Asynchronous JavaScript is everywhere, whether you’re using Ajax, AngularJS, Node.js, or WebRTC. This practical guide shows intermediate to advanced JavaScript developers how Promises can help you manage asynchronous code effectively—including the inevitable flood of callbacks as your codebase grows. You’ll learn the inner workings of Promises and ways to avoid difficulties and missteps when using them. The ability to asynchronously fetch data and load scripts in the browser broadens the capabilities of JavaScript applications. But if you don’t understand how the async part works, you’ll wind up with unpredictable code that’s difficult to maintain. This book is ideal whether you’re new to Promises or want to expand your knowledge of this technology. Understand how async JavaScript works by delving into callbacks, the event loop, and threading Learn how Promises organize callbacks into discrete steps that are easier to read and maintain Examine scenarios you’ll encounter and techniques you can use when writing real-world applications Use features in the Bluebird library and jQuery to work with Promises Learn how the Promise API handles asynchronous errors Explore ECMAScript 6 language features that simplify Promise-related code

Eloquent JavaScript, 3rd Edition

Author: Marijn Haverbeke
Publisher: No Starch Press
ISBN: 1593279507
Category : Computers
Languages : en
Pages : 474

Book Description
Completely revised and updated, this best-selling introduction to programming in JavaScript focuses on writing real applications. JavaScript lies at the heart of almost every modern web application, from social apps like Twitter to browser-based game frameworks like Phaser and Babylon. Though simple for beginners to pick up and play with, JavaScript is a flexible, complex language that you can use to build full-scale applications. This much anticipated and thoroughly revised third edition of Eloquent JavaScript dives deep into the JavaScript language to show you how to write beautiful, effective code. It has been updated to reflect the current state of Java¬Script and web browsers and includes brand-new material on features like class notation, arrow functions, iterators, async functions, template strings, and block scope. A host of new exercises have also been added to test your skills and keep you on track. As with previous editions, Haverbeke continues to teach through extensive examples and immerses you in code from the start, while exercises and full-chapter projects give you hands-on experience with writing your own programs. You start by learning the basic structure of the JavaScript language as well as control structures, functions, and data structures to help you write basic programs. Then you'll learn about error handling and bug fixing, modularity, and asynchronous programming before moving on to web browsers and how JavaScript is used to program them. As you build projects such as an artificial life simulation, a simple programming language, and a paint program, you'll learn how to: - Understand the essential elements of programming, including syntax, control, and data - Organize and clarify your code with object-oriented and functional programming techniques - Script the browser and make basic web applications - Use the DOM effectively to interact with browsers - Harness Node.js to build servers and utilities Isn't it time you became fluent in the language of the Web? * All source code is available online in an inter¬active sandbox, where you can edit the code, run it, and see its output instantly.

You Don't Know JS: Async & Performance

Author: Kyle Simpson
Publisher: "O'Reilly Media, Inc."
ISBN: 1491905204
Category : Computers
Languages : en
Pages : 317

Book Description
No matter how much experience you have with JavaScript, odds are you don’t fully understand the language. As part of the "You Don’t Know JS" series, this concise yet in-depth guide focuses on new asynchronous features and performance techniques—including Promises, generators, and Web Workers—that let you create sophisticated single-page web applications and escape callback hell in the process. Like other books in this series, You Don’t Know JS: Async & Performance dives into trickier parts of the language that many JavaScript programmers simply avoid. Armed with this knowledge, you can become a true JavaScript master. With this book you will: Explore old and new JavaScript methods for handling asynchronous programming Understand how callbacks let third parties control your program’s execution Address the "inversion of control" issue with JavaScript Promises Use generators to express async flow in a sequential, synchronous-looking fashion Tackle program-level performance with Web Workers, SIMD, and asm.js Learn valuable resources and techniques for benchmarking and tuning your expressions and statements

Async & Performance

Author: Kyle Simpson
Publisher: O'Reilly Media
ISBN: 9781491904220
Category : Application software
Languages : en
Pages : 0

Book Description
This book focuses on the new asynchronous features in JavaScript, which are new and confusing to developers. The book covers promises, generators, and coroutines, all of which allow developers to created more sophisticated single-page web applications that provide the features of a desktop application without tying up the user's browser.

JavaScript ASYNC

Author: Ian Elliot
Publisher:
ISBN: 9781871962567
Category :
Languages : en
Pages :

Book Description
Asynchronous programming is essential to the modern web and at last JavaScript programmers have the tools to do the job - the Promise object and the async and await commands. These are so elegant in their design that you need to know about them if only to be impressed. It is likely that other languages will incorporate similar facilities in the future. While async and await make asynchronous code as easy to use as synchronous code there are a lot of subtle things going on and to really master the situation you need to know about Promises and you need to know how the JavaScript dispatch queue works. Written for experienced JavaScript developers who want to get to grips with the complexities of the language, JavaScript Async guides you through the story of async. It starts with Events, which is where asynchronous programming originates, but it quickly becomes apparent that you need additional ways of dealing with long running tasks. The most basic solution is the callback and this is where async programming starts to become difficult. JavaScript used to be a single-threaded language, but with the introduction of the Web Worker you can write multi-threaded programs. Promises are the pinnacle of async programming in JavaScript and putting them together with the dispatch queue provides further advances. The way that async and await work with Promises is nothing short of amazing. The book concludes with a look at how async and await integrate with some of the latest JavaScript APIs that are based on the Promise object. The Service Worker is possibly the biggest change in the way JavaScript can be used to create programs that are just as happy being offline as online. Working with async can be confusing and disorienting, but by combining code examples and lucid explanations Ian Elliot presents a coherent explanation. If you want to work with async read this book first.

JavaScript

Author: T. J. Crowder
Publisher: John Wiley & Sons
ISBN: 1119367956
Category : Computers
Languages : en
Pages : 608

Book Description
All of JavaScript's newest features, in depth, made easy to understand. JavaScript is a rapidly changing language and it can be challenging to keep up with all the new toys being added. JavaScript: The New Toys explores the newest features of the world's most popular programming language while also showing readers how to track what's coming next. After setting the stage by covering who manages the process of improving JavaScript, how new features get introduced, terminology, and a high-level overview of new features, it details each new or updated item in depth, with example uses, possible pitfalls, and expert recommendations for updating old habits in light of new features. JavaScript: The New Toys: Covers all the additions to JavaScript in ES2015-ES2020 plus a preview of what's coming next Explores the latest syntax: nullish coalescing, optional chaining, let and const, class syntax, private methods, private fields, new.target, numeric separators, BigInt, destructuring, default parameters, arrow functions, async functions, await, generator functions, ... (rest and spread), template literals, binary and octal literals, ** (exponentiation), computed property/method names, for-of, for-await-of, shorthand properties, and others Details the new features and patterns including modules, promises, iteration, generators, Symbol, Proxy, reflection, typed arrays, Atomics, shared memory, WeakMap, WeakSet, and more Highlights common pitfalls and explains how to avoid them Shows how to follow the improvements process and even participate in the process yourself Explains how to use new features even before they're widely supported With its comprehensive coverage and friendly, accessible style, JavaScript: The New Toys provides an invaluable resource for programmers everywhere, whether they work in web development, Node.js, Electron, Windows Universal Apps, or another JavaScript environment.

You Don't Know JS: Scope & Closures

Author: Kyle Simpson
Publisher: "O'Reilly Media, Inc."
ISBN: 144933556X
Category : Computers
Languages : en
Pages : 98

Book Description
No matter how much experience you have with JavaScript, odds are you don’t fully understand the language. This concise yet in-depth guide takes you inside scope and closures, two core concepts you need to know to become a more efficient and effective JavaScript programmer. You’ll learn how and why they work, and how an understanding of closures can be a powerful part of your development skillset. Like other books in the "You Don’t Know JS" series, Scope and Closures dives into trickier parts of the language that many JavaScript programmers simply avoid. Armed with this knowledge, you can achieve true JavaScript mastery. Learn about scope, a set of rules to help JavaScript engines locate variables in your code Go deeper into nested scope, a series of containers for variables and functions Explore function- and block-based scope, “hoisting”, and the patterns and benefits of scope-based hiding Discover how to use closures for synchronous and asynchronous tasks, including the creation of JavaScript libraries

You Don't Know JS: Async & Performance

Author: Kyle Simpson
Publisher: "O'Reilly Media, Inc."
ISBN: 1491905212
Category : Computers
Languages : en
Pages : 295