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Professional JavaScript

You're reading from   Professional JavaScript Fast-track your web development career using the powerful features of advanced JavaScript

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Product type Paperback
Published in Sep 2019
Publisher
ISBN-13 9781838820213
Length 664 pages
Edition 1st Edition
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Authors (4):
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Hugo Di Francesco Hugo Di Francesco
Author Profile Icon Hugo Di Francesco
Hugo Di Francesco
Siyuan Gao Siyuan Gao
Author Profile Icon Siyuan Gao
Siyuan Gao
Vinicius Isola Vinicius Isola
Author Profile Icon Vinicius Isola
Vinicius Isola
Philip Kirkbride Philip Kirkbride
Author Profile Icon Philip Kirkbride
Philip Kirkbride
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Toc

Table of Contents (12) Chapters Close

Preface 1. JavaScript, HTML, and the DOM 2. Node.js and npm FREE CHAPTER 3. Node.js APIs and Web Scraping 4. RESTful APIs with Node.js 5. Modular JavaScript 6. Code Quality 7. Advanced JavaScript 8. Asynchronous Programming 9. Event-Driven Programming and Built-In Modules 10. Functional Programming with JavaScript Appendix

Maps and Sets

Maps and Sets are very underrated types in JavaScript, but they can be very powerful in some applications. Maps work just like a basic hashmap in JavaScript, and are useful when you need to keep track of a list of key-value pairs. Sets are used when you need to keep a list of unique values. Most developers often use objects for everything while forgetting that, in some cases, using Maps and Sets is way more efficient. In the following section, we will go over Maps and Sets and how to use them.

There are many cases where we must keep track of a list of unique key-value pairs in our application. When programming with other languages, we often need to implement a class called Hashmap. In JavaScript, there are two types that can accomplish this: one is Map and the other is Object. Because they seem to do the same thing, many JavaScript developers tend to use Object for everything while ignoring that using Map is sometimes way more effective for their use case.

Exercise...

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