Book Image

Mastering JavaScript

By : Ved Antani
Book Image

Mastering JavaScript

By: Ved Antani

Overview of this book

JavaScript is a high-level, dynamic, untyped, lightweight, and interpreted programming language. Along with HTML and CSS, it is one of the three essential technologies of World Wide Web content production, and is an open source and cross-platform technology. The majority of websites employ JavaScript, and it is well supported by all modern web browsers without plugins. However, the JavaScript landscape has changed dramatically in recent years, and you need to adapt to the new world of JavaScript that people now expect. Mastering modern JavaScript techniques and the toolchain are essential to develop web-scale applications. Mastering JavaScript will be your companion as you master JavaScript and build innovative web applications. To begin with, you will get familiarized with the language constructs and how to make code easy to organize. You will gain a concrete understanding of variable scoping, loops, and best practices on using types and data structures, as well as the coding style and recommended code organization patterns in JavaScript. The book will also teach you how to use arrays and objects as data structures. You will graduate from intermediate-level skills to advanced techniques as you come to understand crucial language concepts and design principles. You will learn about modern libraries and tools so you can write better code. By the end of the book, you will understand how reactive JavaScript is going to be the new paradigm.
Table of Contents (16 chapters)
Mastering JavaScript
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

A function literal


One of the most important concepts in JavaScript is that the functions are the primary unit of execution. Functions are the pieces where you will wrap all your code, hence they will give your programs a structure.

JavaScript functions are declared using a function literal.

Function literals are composed of the following four parts:

  • The function keyword.

  • An optional name that, if specified, must be a valid JavaScript identifier.

  • A list of parameter names enclosed in parentheses. If there are no parameters to the function, you need to provide empty parentheses.

  • The body of the function as a series of JavaScript statements enclosed in braces.

A function declaration

The following is a very trivial example to demonstrate all the components of a function declaration:

function add(a,b){
  return a+b;
}
c = add(1,2);
console.log(c);  //prints 3

The declaration begins with a function keyword followed by the function name. The function name is optional. If a function is not given a name,...