Book Image

Learning JavaScript Data Structures and Algorithms - Third Edition

Book Image

Learning JavaScript Data Structures and Algorithms - Third Edition

Overview of this book

A data structure is a particular way of organizing data in a computer to utilize resources efficiently. Data structures and algorithms are the base of every solution to any programming problem. With this book, you will learn to write complex and powerful code using the latest ES 2017 features. Learning JavaScript Data Structures and Algorithms begins by covering the basics of JavaScript and introduces you to ECMAScript 2017, before gradually moving on to the most important data structures such as arrays, queues, stacks, and linked lists. You will gain in-depth knowledge of how hash tables and set data structures function as well as how trees and hash maps can be used to search files in an HD or represent a database. This book serves as a route to take you deeper into JavaScript. You’ll also get a greater understanding of why and how graphs, one of the most complex data structures, are largely used in GPS navigation systems in social networks. Toward the end of the book, you’ll discover how all the theories presented in this book can be applied to solve real-world problems while working on your own computer networks and Facebook searches.
Table of Contents (22 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

ECMAScript 2015+ functionalities


In this topic, we will demonstrate how to use some of the functionalities of ES2015, which may be useful in everyday JavaScript coding and which will also be useful to simplify the examples presented in the following chapters of this book.

Among the functionalities, we will cover the following:

  • Variables with let and const
  • Template literals
  • Destructuring
  • Spread operator
  • Arrow functions using =>
  • Classes
  • Modules

let and const instead of var

Until ES5, we could declare variables in any place in our code, even if we overwrote the variables declaration, as in the following code:

var framework = 'Angular'; 
var framework = 'React'; 
console.log(framework); 

The output of the preceding code is React, as the last variable declared, named framework, was assigned this value. In the previous code, we had two variables with the same name; this is very dangerous and might drive the code to an incorrect output.

Other languages, such as C, Java, and C#, do not allow this behavior...