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Professional JavaScript for Web Developers

You're reading from   Professional JavaScript for Web Developers Discover an easy-to-learn guide to upgrade your JavaScript skills

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Product type Paperback
Published in Nov 2019
Publisher Wiley
ISBN-13 9781119366447
Length 1144 pages
Edition 4th Edition
Languages
Tools
Concepts
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Author (1):
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Matt Frisbie Matt Frisbie
Author Profile Icon Matt Frisbie
Matt Frisbie
Matt Frisbie has worked in web development for over a decade. During that time, he's been a startup co-founder, an engineer at a Big Four tech company, and the first engineer at a Y Combinator startup that would eventually become a billion-dollar company. As a Google software engineer, Matt worked on both the AdSense and Accelerated Mobile Pages (AMP) platforms; his code contributions run on most of the planet's web browsing devices. Prior to this, Matt was the first engineer at DoorDash, where he helped lay the foundation for a company that has become the leader in online food delivery. Matt has written two books and recorded two video series for O'Reilly and Packt, speaks at frontend meetups and web casts, and is a level 1 sommelier. He majored in Computer Engineering at the University of Illinois Urbana-Champaign. Matt's Twitter handle is @mattfriz.
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Table of Contents (37) Chapters Close

COVER FREE CHAPTER
FOREWORD
INTRODUCTION 1 What Is JavaScript? 2 JavaScript in HTML 3 Language Basics 4 Variables, Scope, and Memory 5 Basic Reference Types 6 Collection Reference Types 7 Iterators and Generators 8 Objects, Classes, and Object-Oriented Programming 9 Proxies and Reflect 10 Functions 11 Promises and Async Functions 12 The Browser Object Model 13 Client Detection 14 The Document Object Model 15 DOM Extensions 16 DOM Levels 2 and 3 17 Events 18 Animation and Graphics with Canvas 19 Scripting Forms 20 JavaScript APIs 21 Error Handling and Debugging 22 XML in JavaScript 23 JSON 24 Network Requests and Remote Resources 25 Client-Side Storage 26 Modules 27 Workers 28 Best Practices A ES2018 and ES2019 B Strict Mode C JavaScript Libraries and Frameworks D JavaScript Tools INDEX
END USER LICENSE AGREEMENT

4
Variables, Scope, and Memory

WHAT'S IN THIS CHAPTER?

  • Working with primitive and reference values in variables
  • Understanding execution context
  • Understanding garbage collection

WROX.COM DOWNLOADS FOR THIS CHAPTER

Please note that all the code examples for this chapter are available as a part of this chapter's code download on the book's website at www.wrox.com/go/projavascript4e on the Download Code tab.

The nature of variables in JavaScript, as defined in ECMA-262, is quite unique compared to that of other languages. Being loosely typed, a variable is literally just a name for a particular value at a particular time. Because there are no rules defining the type of data that a variable must hold, a variable's value and data type can change during the lifetime of a script. Though this is an interesting, powerful, and problematic feature, there are many more complexities related to variables.

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Authors (1)

Profile icon Matt Frisbie
Matt Frisbie
Matt Frisbie has worked in web development for over a decade. During that time, he's been a startup co-founder, an engineer at a Big Four tech company, and the first engineer at a Y Combinator startup that would eventually become a billion-dollar company. As a Google software engineer, Matt worked on both the AdSense and Accelerated Mobile Pages (AMP) platforms; his code contributions run on most of the planet's web browsing devices. Prior to this, Matt was the first engineer at DoorDash, where he helped lay the foundation for a company that has become the leader in online food delivery. Matt has written two books and recorded two video series for O'Reilly and Packt, speaks at frontend meetups and web casts, and is a level 1 sommelier. He majored in Computer Engineering at the University of Illinois Urbana-Champaign. Matt's Twitter handle is @mattfriz.
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See other products by Matt Frisbie
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