book

Practical Modern JavaScript

by Nicolas Bevacqua

June 2017

Intermediate to advanced

334 pages

7h 10m

English

O'Reilly Media, Inc.

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Who Should Read This BookWhy Modern JavaScript?How Is This Book Organized?Conventions Used in This BookO’Reilly SafariHow to Contact UsAcknowledgments
1.1 A Brief History of JavaScript Standards1.2 ECMAScript as a Rolling Standard1.3 Browser Support and Complementary Tooling1.3.1 Introduction to the Babel Transpiler1.3.2 Code Quality and Consistency with ESLint1.4 Feature Themes in ES61.5 Future of JavaScript
2.1 Object Literals2.1.1 Property Value Shorthands2.1.2 Computed Property Names2.1.3 Method Definitions2.2 Arrow Functions2.2.1 Lexical Scoping2.2.2 Arrow Function Flavors2.2.3 Merits and Use Cases2.3 Assignment Destructuring2.3.1 Destructuring Objects2.3.2 Destructuring Arrays2.3.3 Function Parameter Defaults2.3.4 Function Parameter Destructuring2.3.5 Use Cases for Destructuring2.4 Rest Parameter and Spread Operator2.4.1 Rest Parameters2.4.2 Spread Operator2.5 Template Literals2.5.1 String Interpolation2.5.2 Multiline Template Literals2.5.3 Tagged Templates2.6 let and const Statements2.6.1 Block Scoping and let Statements2.6.2 Temporal Dead Zone2.6.3 Const Statements2.6.4 Merits of const and let
3.1 Classes3.1.1 Class Fundamentals3.1.2 Properties and Methods in Classes3.1.3 Extending JavaScript Classes3.2 Symbols3.2.1 Local Symbols3.2.2 Practical Use Cases for Symbols3.2.3 Global Symbol Registry3.2.4 Well-Known Symbols3.3 Object Built-in Improvements3.3.1 Extending Objects with Object.assign3.3.2 Comparing Objects with Object.is3.3.3 Object.setPrototypeOf3.4 Decorators3.4.1 A Primer on JavaScript Decorators3.4.2 Stacking Decorators and a Warning About Immutability3.4.3 Use Case By Example: Attributes in C#3.4.4 Marking Properties in JavaScript
4.1 Promises4.1.1 Getting Started with Promises4.1.2 Promise Continuation and Chaining4.1.3 Creating a Promise from Scratch4.1.4 Promise States and Fates4.1.5 Promise#finally Proposal4.1.6 Leveraging Promise.all and Promise.race4.2 Iterator Protocol and Iterable Protocol4.2.1 Understanding Iteration Principles4.2.2 Infinite Sequences4.2.3 Iterating Object Maps as Key/Value Pairs4.2.4 Building Versatility Into Iterating a Playlist4.3 Generator Functions and Generator Objects4.3.1 Generator Fundamentals4.3.2 Iterating over Generators by Hand4.3.3 Mixing Generators into Iterables4.3.4 Tree Traversal Using Generators4.3.5 Consuming Generator Functions for Flexibility4.3.6 Dealing with Asynchronous Flows4.3.7 Throwing Errors at a Generator4.3.8 Returning on Behalf of a Generator4.3.9 Asynchronous I/O Using Generators4.4 Async Functions4.4.1 Flavors of Async Code4.4.2 Using async/await4.4.3 Concurrent Async Flows4.4.4 Error Handling4.4.5 Understanding Async Function Internals4.5 Asynchronous Iteration4.5.1 Async Iterators4.5.2 Async Generators
5.1 Using ES6 Maps5.1.1 First Look into ES6 Maps5.1.2 Hash-Maps and the DOM5.2 Understanding and Using WeakMap5.2.1 Is WeakMap a Worse Map?5.3 Sets in ES65.4 ES6 WeakSets
6.1 Getting Started with Proxy6.1.1 Trapping get Accessors6.1.2 Trapping set Accessors6.1.3 Schema Validation with Proxies6.2 Revocable Proxies6.3 Proxy Trap Handlers6.3.1 has Trap6.3.2 deleteProperty Trap6.3.3 defineProperty Trap6.3.4 ownKeys Trap6.4 Advanced Proxy Traps6.4.1 getOwnPropertyDescriptor Trap6.4.2 apply Trap6.4.3 construct Trap6.4.4 getPrototypeOf Trap6.4.5 setPrototypeOf Trap6.4.6 preventExtensions Trap6.4.7 isExtensible Trap
7.1 Numbers7.1.1 Binary and Octal Literals7.1.2 Number.isNaN7.1.3 Number.isFinite7.1.4 Number.parseInt7.1.5 Number.parseFloat7.1.6 Number.isInteger7.1.7 Number.EPSILON7.1.8 Number.MAX_SAFE_INTEGER and Number.MIN_SAFE_INTEGER7.1.9 Number.isSafeInteger7.2 Math7.2.1 Math.sign7.2.2 Math.trunc7.2.3 Math.cbrt7.2.4 Math.expm17.2.5 Math.log1p7.2.6 Math.log107.2.7 Math.log27.2.8 Trigonometric Functions7.2.9 Math.hypot7.2.10 Bitwise Computation Helpers7.3 Strings and Unicode7.3.1 String#startsWith7.3.2 String#endsWith7.3.3 String#includes7.3.4 String#repeat7.3.5 String Padding and Trimming7.3.6 Unicode7.3.7 String.prototype[Symbol.iterator]7.3.8 A Proposal to Split Grapheme Segments7.3.9 String#codePointAt7.3.10 String.fromCodePoint7.3.11 Unicode-Aware String Reversal7.3.12 String#normalize7.4 Regular Expressions7.4.1 Sticky Matching Flag /y7.4.2 Unicode Flag /u7.4.3 Named Capture Groups7.4.4 Unicode Property Escapes7.4.5 Lookbehind Assertions7.4.6 A New /s “dotAll” Flag7.4.7 String#matchAll7.5 Array7.5.1 Array.from7.5.2 Array.of7.5.3 Array#copyWithin7.5.4 Array#fill7.5.5 Array#find and Array#findIndex7.5.6 Array#keys7.5.7 Array#values7.5.8 Array#entries7.5.9 Array.prototype[Symbol.iterator]
8.1 CommonJS8.2 JavaScript Modules8.2.1 Strict Mode8.2.2 export Statements8.2.3 import Statements8.2.4 Dynamic import()8.3 Practical Considerations for ES Modules

9.1 Variable Declarations9.2 Template Literals9.3 Shorthand Notation and Object Destructuring9.4 Rest and Spread9.5 Savoring Function Flavors9.6 Classes and Proxies9.7 Asynchronous Code Flows9.8 Complexity Creep, Abstractions, and Conventions

Overview

To get the most out of modern JavaScript, you need learn the latest features of its parent specification, ECMAScript 6 (ES6). This book provides a highly practical look at ES6, without getting lost in the specification or its implementation details. Armed with practical examples, author Nicolas Bevacqua shows you new ways to deal with asynchronous flow control, declare objects or functions, and create proxies or unique sets, among many other features.

The first title in Bevacqua’s Modular JavaScript series, Practical Modern JavaScript prepares JavaScript and Node.js developers for applied lessons in modular design, testing, and deployment in subsequent books.

This book explains:

How JavaScript and its standards development process have evolved
Essential ES6 changes, including arrow functions, destructuring, let and const
Class syntax for declaring object prototypes, and the new Symbol primitive
How to handle flow control with Promises, iterators, generators, and async functions
ES6 collection built-in types for creating object maps and unique sets
How and when to use the new Proxy and Reflect built-ins
Changes to Array, Math, numbers, strings, Unicode, and regular expressions, and other improvements since ES5