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SECTION 12
Compiling TypeScript to JavaScript
SECTION 13
Union Types, Discriminated Unions, and Type Guards
Beginners Guide to TypeScript
CHAPTER 1
Nested Destructuring
SECTION 1.1
Nested Destructuring
SECTION 1.2
TypeScript Considerations
CHAPTER 2
Building a TypeScript and Node.js App
SECTION 2.1
Building number-app
SECTION 2.2
The html file
SECTION 2.3
Serving the HTML
SECTION 2.4
Trying it out
SECTION 2.5
Building NumInfo
SECTION 2.6
Adding a new route
SECTION 2.7
Handling Form Submissions
SECTION 2.8
Using fetch
SECTION 2.9
Conclusion
CHAPTER 3
ES2015 and TypeScript
SECTION 3.1
ES2015
SECTION 3.2
What We'll Cover Next
CHAPTER 4
Building Attachment and Image for BufferUnderflow
SECTION 4.1
Modeling Attachment and Image
SECTION 4.2
Defining Attachment
SECTION 4.3
Defining the Image
SECTION 4.4
Using ImageFormat
SECTION 4.5
Understanding static
SECTION 4.6
Building a Summary with getSummary
SECTION 4.7
Completed Image Code
SECTION 4.8
Using Image
CHAPTER 5
Abstraction and Polymorphism
SECTION 5.1
Abstraction with Interfaces
SECTION 5.2
Using Polymorphism
SECTION 5.3
Understanding Abstract Classes
SECTION 5.4
Conclusion
CHAPTER 6
Generating the Budget Class
SECTION 6.1
Budget Class
SECTION 6.2
Five New Methods
SECTION 6.3
Category enum
SECTION 6.4
Grouping Expenses in a Budget
SECTION 6.5
Putting It Together
CHAPTER 7
Typing Functions - The Basics
SECTION 7.1
Functions
SECTION 7.2
Annotating Functions
SECTION 7.3
Optional Parameters
SECTION 7.4
Default Parameters
SECTION 7.5
Rest Parameters
CHAPTER 8
TypeScript Language Features
SECTION 8.1
Introduction
SECTION 8.2
Type Alias
SECTION 8.3
Primitive Types
SECTION 8.4
Number
SECTION 8.5
String
SECTION 8.6
Boolean
SECTION 8.7
null and undefined
SECTION 8.8
void
CHAPTER 9
Typing Objects
SECTION 9.1
Object Types
SECTION 9.2
The object type
SECTION 9.3
Typing object properties
SECTION 9.4
Optional properties
CHAPTER 10
Inheritance and Composition
SECTION 10.1
Inheritance and Composition in TypeScript
SECTION 10.2
Benefits of Inheritance
SECTION 10.3
Where Inheritance Fails
SECTION 10.4
Favor Composition
CHAPTER 11
Where To Go From Here
SECTION 11.1
TypeScript and React
SECTION 11.2
TypeScript and Angular
SECTION 11.3
TypeScript and GraphQL
SECTION 11.4
Let us know what you think!
CHAPTER 12
Compiling TypeScript to JavaScript
SECTION 12.1
Compiling to JavaScript
SECTION 12.2
Compiler Options
CHAPTER 13
Union Types, Discriminated Unions, and Type Guards
SECTION 13.1
Union Types Denote "or"
SECTION 13.2
Discriminated Unions
SECTION 13.3
Type Guards
CHAPTER 14
Intersection Types
SECTION 14.1
Intersection Types Express "and"
SECTION 14.2
Optional Properties are Optional
SECTION 14.3
Shared Properties are Intersections
CHAPTER 15
Introduction to TypeScript and Node.js
SECTION 15.1
Introduction
SECTION 15.2
Working With The File System
SECTION 15.3
Configuring Development Environment
SECTION 15.4
Building fs-json
SECTION 15.5
Typed JSON files
SECTION 15.6
Express and TypeScript
SECTION 15.7
Configuring Development Environment
CHAPTER 16
let and const in TypeScript
SECTION 16.1
let and const
SECTION 16.2
TypeScript Considerations
CHAPTER 17
Tracking Expenses by Month and Users
SECTION 17.1
TrackedMonth Class
SECTION 17.2
User Class
SECTION 17.3
Conclusion
CHAPTER 18
Generating Unique Ids
SECTION 18.1
Generating Unique Ids For Each Expense
SECTION 18.2
Add genUniqueId to Expense
SECTION 18.3
Putting It Together
CHAPTER 19
Destructuring Assignment
SECTION 19.1
Destructuring Assignment
SECTION 19.2
Destructuring Arrays
SECTION 19.3
Destructuring Objects
CHAPTER 20
Object Oriented TypeScript
SECTION 20.1
Introduction
SECTION 20.2
OOP Concepts in TypeScript
SECTION 20.3
Encapsulation
SECTION 20.4
Information Hiding
CHAPTER 21
Classes in TypeScript: User and Expense
SECTION 21.1
TypeScript Classes
SECTION 21.2
Expense Class
CHAPTER 22
Typing Functions with Overloading, Values, and Arrow Functions
SECTION 22.1
Overloading
SECTION 22.2
Functions as values
SECTION 22.3
Arrow functions
CHAPTER 23
Running BufferUnderflow
SECTION 23.1
The Simulation Code
SECTION 23.2
The Output
SECTION 23.3
Conclusion and Review
CHAPTER 24
Planning Our First TypeScript Application: FinanceMe
SECTION 24.1
Building FinanceMe
SECTION 24.2
Planning FinanceMe
SECTION 24.3
Example Usage
SECTION 24.4
Class Diagram of FinanceMe
CHAPTER 25
Enhanced Object Literals
SECTION 25.1
Enhanced Object Literals
SECTION 25.2
Shorthand for property names
SECTION 25.3
Shorthand for method names
SECTION 25.4
Computed property names
SECTION 25.5
TypeScript Considerations
CHAPTER 26
Building the Question and Answer Models
SECTION 26.1
Modeling Question and Answer
SECTION 26.2
Building the Answer Model
SECTION 26.3
Generating a Summary
SECTION 26.4
Improving addAnswer
SECTION 26.5
Adding Private Setters
SECTION 26.6
Completed Answer Class
SECTION 26.7
Defining the Question Class
SECTION 26.8
Setting Answers
CHAPTER 27
Imports and Exports with TypeScript Modules
SECTION 27.1
TypeScript Modules
SECTION 27.2
Named Exports and Imports
SECTION 27.3
Default Exports and Imports
CHAPTER 28
Lists with Arrays and Tuples
SECTION 28.1
Arrays
SECTION 28.2
Tuples
SECTION 28.3
Optional Elements
CHAPTER 29
Building the User Model
SECTION 29.1
User.ts
SECTION 29.2
Adding Questions and Answers
SECTION 29.3
Getting the SUmmary
SECTION 29.4
Permissions
SECTION 29.5
The Finished User
SECTION 29.6
Using the User model
CHAPTER 30
Getting Started With TypeScript
SECTION 30.1
Introduction
SECTION 30.2
What is TypeScript?
SECTION 30.3
JavaScript vs. TypeScript Example
SECTION 30.4
Untyped JavaScript
SECTION 30.5
Catching Errors with Types
SECTION 30.6
Why Should I Use TypeScript?
CHAPTER 31
Object Oriented in Practice with BufferUnderflow
SECTION 31.1
Introduction
SECTION 31.2
Code Examples
SECTION 31.3
Unique Entity
SECTION 31.4
getUniqueId
SECTION 31.5
Summary Interface
SECTION 31.6
Using the Interfaces
CHAPTER 32
Setting Up Your TypeScript Development Environment
SECTION 32.1
Setting up your development environment
SECTION 32.2
Getting Started
CHAPTER 33
Spread Operator
SECTION 33.1
Spread Operator
SECTION 33.2
Spreading Arrays
SECTION 33.3
Spreading Objects
SECTION 33.4
TypeScript Considerations
CHAPTER 34
Changelog
SECTION 34.1
Revision 3
SECTION 34.2
Revision 2
CHAPTER 35
Enums are for named constants
SECTION 35.1
Enums
SECTION 35.2
Enums have a value
SECTION 35.3
Reverse Mappings
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SECTION 14
Intersection Types
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Union Types, Discriminated Unions, and Type Guards
Table of Contents
Section 13.1
Union Types Denote "or"