دانلود کتاب جاوا اسکریپت بعدی – راهنمای کامل شما برای ویژگی های جدید معرفی شده در جاوا اسکریپت، از ES6 تا ES9

JavaScript is everywhere—it runs single-page applications on the client side, is used on the server side (with technologies like Node.js), helps build desktop applications with Electron,1 and can be used to work with single-board computers like Raspberry Pi.2 JavaScript is even used to train machine-learning models in the browser using technologies like TensorFlow.js.3 All this to say, JavaScript is (arguably) the most deployed language in the world—every desktop and laptop and every phone with an embedded browser can run JavaScript. As it stands today, JavaScript exhibits many of the features that one would expect from a language with this large a footprint. But that wasn’t always the case. JavaScript has a long history, spanning 24 years at the time of this writing. In this time, JavaScript went from being a scripting language used to animate web pages to one that is being used everywhere, and for everything. JavaScript’s reputation, however, preceded itself—it was deemed quirky and error-prone, and not all the criticisms were without merit. And everyone, including the TC39,4 the central committee that is responsible for evolving JavaScript, took notice. In 2015, ES6 was announced, which introduced a slew of new features and syntactic changes to the language. The aim was simple—to usher JavaScript into the modern Web era—armed with the features that developers were vying for, and provide the basis for future editions of the language. The result? A language that aims to improve developer experience, with constructs that seem familiar to developers coming in from other languages. Alongside, a yearly cadence for releasing future editions was announced, ensuring that JavaScript continues to evolve and mature. Features like default parameters, support for variadic functions, destructuring syntax, and fat-arrow functions make it easier to lean into JavaScript’s functional nature, allowing for code that is concise and elegant. Simultaneously, the newly added class syntax makes it possible to build inheritance hierarchies easily, allowing for library and framework authors to provide the necessary “trellis” to hook into, and extend. Asynchronous programming is a natural consequence of JavaScript’s inherent design, and once again, the new additions to JavaScript make things easier. Promises are now a native API, opening the door for a whole new level of abstractions, that we, the developers, can build on. Two such abstractions are async/await, which use promises and help make writing asynchronous code seem almost imperative. And there is much more! All put together, JavaScript today feels like a very different language—one that acts and behaves like other languages that developers might be used to. This book aims to introduce you to all of these features, endeavoring to provide a nuanced view of the “what” and the “why” for every inclusion. However, we cannot learn without doing—so this book provides a slew of examples, each one catered to highlight a specific feature. So, let’s put our developer hats on, fire up our editors, and write some code. This book is directed toward programmers, developers, technical leads, architects, programming hobbyists, or anyone interested in learning about how JavaScript has evolved over the past 5 years. If you are someone who dreads JavaScript development because you have been burnt one too many times by the language, then perhaps this book will demonstrate how the language has been transformed to be more familiar (to programmers comfortable with other languages) and less idiosyncratic.