Javascript Technical Interview Questions
Javascript Technical Interview Questions
Prepare Yourself For That Dream Job
About the Book
You've applied for that Javascript position you've always dreamed about.
There is just one hurdle in your way: the technical interview
You really want that position. You get to play with the coolest new technologies and work with the best people. But you're rightfully worried about the technical interview..
"So," the interviewer asks you,
"Can you explain to me why "true" == true
returns false
? Please explain the steps in detail as well", she continues.
You quake in your boots. You know about truthy and falsey values, but you don't exactly know why a truthy value would return false
. Worse, you need to be able to explain how it happened. If only you had brushed up on your knowledge of Javascript quirks. If only there were a book for such reference. You could have aced this interview.
Know the Whys and Hows
The good news is you still can. Like any interviews, you must prepare for your technical interview, especially so for Javascript, since there are many quirks to Javascript. Do you know them all? Why is eval
and with
frowned upon? Can you explain how variable hoisting happens, step-by-step? In many technical interviews, it is the "why" and "how" questions that kill. Prevent that from happening by preparing yourself. This book is for you. It gives you that deep knowledge required for the harder questions that will inevitably be asked.
It does not matter if the position you are applying is for a jQuery position, or a Node.js position. Javascript's quirks happen on both server-side and client-side. This book covers the quirks found in the language itself. Unlike most other online resources, this book does not treat you like a dummy. It assumes you know your basics (and you should, since you're a rockstar Javascript developer) and merely cover the trickier parts of Javascript. Here are some of the things this book covers:
- Why certain Immediately Invoked Function Expressions don't work?
- Why in some contexts, commas act funnily.
- Why in some cases newlines act funnily.
- Why in some cases, Google Chrome appears to support block-level scoping without ES6 syntax
- Why truthy values are not true, and why falsey values are not false.
- What is the call expression
foo)(
- And many more!
If there is a book that will help you prepare for your Javascript interview, it is this one. Written in a conversational style, it helps you relax while conveying the deepest knowledge of Javascript. Exactly the way you would in an interview.
This book is exactly what you need to ace that interview.
Bundles that include this book
Table of Contents
-
-
How To Read This Book
- What This Book Covers
- Introduction
-
How To Read This Book
-
The Basics
-
The Basics
- What are the types available in JavaScript
-
What is the difference between
null
andundefined
? - Does JavaScript have classical inheritence?
- What is the difference between classical inheritence and prototypal inheritence?
- How are variables in JavaScript scoped?
- What is a closure?
- What is the difference between the Global Object and host object?
- What are module loaders like AMD and CommonJS?
- Other Basic Things You Should Know
-
The Basics
-
The Quirks
-
On IIFE Behaviour
- The Explanation
- Exceptions
- During The Interview
-
On The Comma Operator
- The Explanation
- Miscelleny
- Practice Questions
- During The Interview
-
On “Block Scoping”
- The Explanation
- During The Interview
-
On Truthy and Falsey Things
- The Explanation
- Exceptions
- During The Interview
-
On Automatic Semicolon Insertion
- The Explanation
- The Value of Using Crockford-style IIFE Declarations
- Practice Question
- During The Interview
-
On
new
and Constructors- The Explanation
- Practice Questions
- During The Interview
-
On Object Coercion
- The Explanation
- Practice Questions
- During The Interview
-
On Numbers
- The Explanation
- During The Interview
-
On Regular Expressions
- The Explanation
- During An Interview
-
On Operator Precedence
- The Explanation
- During The Interview
-
On Global Variables
- The Explanation
- During The Interview
-
On Functions And Evaluating Them
- The Explanation
- During The Interview
-
On IIFE Behaviour
-
Bonus Material
-
What Every JavaScript Developer Should Know About Floating Points
- Floating Points
- The Radix Point
- Removing the Radix Point
- IEEE 754
- Rounding Errors
- Handling Floating Points in JavaScript
-
What Every JavaScript Developer Should Know About Floating Points
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