JS◆ The JavaScript Book

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CONTENTS

What is JavaScript?
How JavaScript Runs
JavaScript Engines
Writing Your First JavaScript
Statements
Expressions
Comments

Variables
let
const
var
Values
Primitive Values

Data Types
Strings
Numbers
BigInt
Boolean
Undefined
Null
Symbol

Arithmetic Operators
Assignment Operators
Comparison Operators
Logical Operators
Equality
Strict Equality
Type Coercion
Truthy and Falsy Values
Nullish Coalescing
Optional Chaining
Ternary Operator

if
else
else if
switch
for
while
do while
break
continue

What is a Function?
Function Declaration
Function Expression
Calling Functions
Parameters
Arguments
Return Values
Default Parameters
Rest Parameters
Arrow Functions
Anonymous Functions
Callback Functions
Higher-Order Functions
Pure Functions
Recursion

What is an Object?
Properties
Methods
Object References
Object Destructuring
Spread Syntax

Arrays
Array Indexes
Array Methods
map
filter
reduce
forEach
Array Destructuring
Reference vs Value

What is Scope?
Global Scope
Function Scope
Block Scope
Lexical Scope
Scope Chain
Lexical Environment
Hoisting
Temporal Dead Zone

Closures
How Closures Remember Variables
Practical Uses of Closures

What Happens When JavaScript Runs?
JavaScript Runtime
JavaScript Engine

Execution Context
Global Execution Context
Function Execution Context
Creation Phase
Execution Phase

Call Stack
Stack Overflow

Heap
Memory
Garbage Collection

Event Loop
How the Event Loop Works

Synchronous JavaScript
Asynchronous JavaScript
Blocking vs Non-Blocking
Web APIs
Callbacks
Callback Queue
Microtask Queue
Macrotask Queue

Promises
Promise States
Promise Chaining

async
await

Prototype
Prototype Chain
Inheritance
Constructor Functions

Classes
Class Methods
extends
super
Private Fields

What is `this`?
Global Context
Object Method
Constructor
Explicit Binding
call
apply
bind
Arrow Functions and `this`

Modules
import
export
ES Modules
CommonJS

Strict Mode
Error Handling
try
catch
finally
Custom Errors

Iterators
Generators
Symbols
WeakMap
WeakSet
Event Delegation
Debouncing
Throttling

Chapter XVIII

Async / Await

This chapter covers 2 topics. Work through them in order, or jump to the one you need.

Topics in this chapter

01 async
02 await

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