Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Object-Oriented JavaScript

You're reading from   Object-Oriented JavaScript Learn everything you need to know about object-oriented JavaScript (OOJS)

Arrow left icon
Product type Paperback
Published in Jan 2017
Publisher Packt
ISBN-13 9781785880568
Length 550 pages
Edition 3rd Edition
Languages
Tools
Arrow right icon
Authors (2):
Arrow left icon
Stoyan STEFANOV Stoyan STEFANOV
Author Profile Icon Stoyan STEFANOV
Stoyan STEFANOV
Ved Antani Ved Antani
Author Profile Icon Ved Antani
Ved Antani
Arrow right icon
View More author details
Toc

Table of Contents (19) Chapters Close

Preface 1. Object-Oriented JavaScript FREE CHAPTER 2. Primitive Data Types, Arrays, Loops, and Conditions 3. Functions 4. Objects 5. ES6 Iterators and Generators 6. Prototype 7. Inheritance 8. Classes and Modules 9. Promises and Proxies 10. The Browser Environment 11. Coding and Design Patterns 12. Testing and Debugging 13. Reactive Programming and React A. Reserved Words B. Built-in Functions
C. Built-in Objects D. Regular Expressions
E. Answers to Exercise Questions

Functions are data


Functions in JavaScript are actually data. This is an important concept that we'll need later on. This means that you can create a function and assign it to a variable, as follows:

    var f = function () { 
      return 1; 
    }; 

This way of defining a function is sometimes referred to as function literal notation.

The function () { return 1;} part is a function expression. A function expression can optionally have a name, in which case it becomes a named function expression (NFE). So, this is also allowed, although rarely seen in practice (and causes IE to mistakenly create two variables in the enclosing scope-f and myFunc):

    var f = function myFunc() { 
      return 1; 
    }; 

As you can see, there's no difference between a named function expression and a function declaration. But they are, in fact, different. The only way to distinguish between the two is to look at the context in which they are used. Function declarations may only...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime