TypeScript Cookbook: Real World Type-Level Programming

Cover
Copyright
Table of Contents
Foreword
Preface
	Who This Book Is For
	What’s in This Book?
	Organization of This Book
	Conventions Used in This Book
		Programming Conventions
		Typesetting Conventions
	Using Code Examples
	O’Reilly Online Learning
	How to Contact Us
	Acknowledgments
Chapter 1. Project Setup
	1.1 Type-Checking JavaScript
		Problem
		Solution
		Discussion
	1.2 Installing TypeScript
		Problem
		Solution
		Discussion
	1.3 Keeping Types on the Side
		Problem
		Solution
		Discussion
	1.4 Migrating a Project to TypeScript
		Problem
		Solution
		Discussion
	1.5 Loading Types from Definitely Typed
		Problem
		Solution
		Discussion
	1.6 Setting Up a Full-Stack Project
		Problem
		Solution
		Discussion
	1.7 Setting Up Tests
		Problem
		Solution
		Discussion
	1.8 Typing ECMAScript Modules from URLs
		Problem
		Solution
		Discussion
	1.9 Loading Different Module Types in Node
		Problem
		Solution
		Discussion
	1.10 Working with Deno and Dependencies
		Problem
		Solution
		Discussion
	1.11 Using Predefined Configurations
		Problem
		Solution
		Discussion
Chapter 2. Basic Types
	2.1 Annotating Effectively
		Problem
		Solution
		Discussion
	2.2 Working with any and unknown
		Problem
		Solution
		Discussion
	2.3 Choosing the Right Object Type
		Problem
		Solution
		Discussion
	2.4 Working with Tuple Types
		Problem
		Solution
		Discussion
	2.5 Understanding Interfaces Versus Type Aliases
		Problem
		Solution
		Discussion
	2.6 Defining Function Overloads
		Problem
		Solution
		Discussion
	2.7 Defining this Parameter Types
		Problem
		Solution
		Discussion
	2.8 Working with Symbols
		Problem
		Solution
		Discussion
	2.9 Understanding Value and Type Namespaces
		Problem
		Solution
		Discussion
Chapter 3. The Type System
	3.1 Modeling Data with Union and Intersection Types
		Problem
		Solution
		Discussion
	3.2 Explicitly Defining Models with Discriminated Union Types
		Problem
		Solution
		Discussion
	3.3 Exhaustiveness Checking with the Assert never Technique
		Problem
		Solution
		Discussion
	3.4 Pinning Types with Const Context
		Problem
		Solution
		Discussion
	3.5 Narrowing Types with Type Predicates
		Problem
		Solution
		Discussion
	3.6 Understanding void
		Problem
		Solution
		Discussion
	3.7 Dealing with Error Types in catch Clauses
		Problem
		Solution
		Discussion
	3.8 Creating Exclusive Or Models with Optional never
		Problem
		Solution
		Discussion
	3.9 Effectively Using Type Assertions
		Problem
		Solution
		Discussion
	3.10 Using Index Signatures
		Problem
		Solution
		Discussion
	3.11 Distinguishing Missing Properties and Undefined Values
		Problem
		Solution
		Discussion
	3.12 Working with Enums
		Problem
		Solution
		Discussion
	3.13 Defining Nominal Types in a Structural Type System
		Problem
		Solution
		Discussion
	3.14 Enabling Loose Autocomplete for String Subsets
		Problem
		Solution
		Discussion
Chapter 4. Generics
	4.1 Generalizing Function Signatures
		Problem
		Solution
		Discussion
	4.2 Creating Related Function Arguments
		Problem
		Solution
		Discussion
	4.3 Getting Rid of any and unknown
		Problem
		Solution
		Discussion
	4.4 Understanding Generic Instantiation
		Problem
		Solution
		Discussion
	4.5 Generating New Object Types
		Problem
		Solution
		Discussion
	4.6 Modifying Objects with Assertion Signatures
		Problem
		Solution
		Discussion
	4.7 Mapping Types with Type Maps
		Problem
		Solution
		Discussion
	4.8 Using ThisType to Define this in Objects
		Problem
		Solution
		Discussion
	4.9 Adding Const Context to Generic Type Parameters
		Problem
		Solution
		Discussion
Chapter 5. Conditional Types
	5.1 Managing Complex Function Signatures
		Problem
		Solution
		Discussion
	5.2 Filtering with never
		Problem
		Solution
		Discussion
	5.3 Grouping Elements by Kind
		Problem
		Solution
		Discussion
	5.4 Removing Specific Object Properties
		Problem
		Solution
		Discussion
	5.5 Inferring Types in Conditionals
		Problem
		Solution
		Discussion
Chapter 6. String Template Literal Types
	6.1 Defining a Custom Event System
		Problem
		Solution
		Discussion
	6.2 Creating Event Callbacks with String Manipulation Types and Key Remapping
		Problem
		Solution
		Discussion
	6.3 Writing a Formatter Function
		Problem
		Solution
		Discussion
	6.4 Extracting Format Parameter Types
		Problem
		Solution
		Discussion
	6.5 Dealing with Recursion Limits
		Problem
		Solution
		Discussion
	6.6 Using Template Literals as Discriminants
		Problem
		Solution
		Discussion
Chapter 7. Variadic Tuple Types
	7.1 Typing a concat Function
		Problem
		Solution
		Discussion
	7.2 Typing a promisify Function
		Problem
		Solution
		Discussion
	7.3 Typing a curry Function
		Problem
		Solution
		Discussion
	7.4 Typing a Flexible curry Function
		Problem
		Solution
		Discussion
	7.5 Typing the Simplest curry function
		Problem
		Solution
		Discussion
	7.6 Creating an Enum from a Tuple
		Problem
		Solution
		Discussion
	7.7 Splitting All Elements of a Function Signature
		Problem
		Solution
		Discussion
Chapter 8. Helper Types
	8.1 Setting Specific Properties Optional
		Problem
		Solution
		Discussion
	8.2 Modifying Nested Objects
		Problem
		Solution
		Discussion
	8.3 Remapping Types
		Problem
		Solution
		Discussion
	8.4 Getting All Required Keys
		Problem
		Solution
		Discussion
	8.5 Allowing at Least One Property
		Problem
		Solution
		Discussion
	8.6 Allowing Exactly One and All or None
		Problem
		Solution
		Discussion
	8.7 Converting Union to Intersection Types
		Problem
		Solution
		Discussion
	8.8 Using type-fest
		Problem
		Solution
		Discussion
Chapter 9. The Standard Library and External Type Definitions
	9.1 Iterating over Objects with Object.keys
		Problem
		Solution
		Discussion
	9.2 Explicitly Highlighting Unsafe Operations with Type Assertions and unknown
		Problem
		Solution
		Discussion
	9.3 Working with defineProperty
		Problem
		Solution
		Discussion
	9.4 Expanding Types for Array.prototype.includes
		Problem
		Solution
		Discussion
	9.5 Filtering Nullish Values
		Problem
		Solution
		Discussion
	9.6 Extending Modules
		Problem
		Solution
		Discussion
	9.7 Augmenting Globals
		Problem
		Solution
		Discussion
	9.8 Adding Non-JS Modules to the Module Graph
		Problem
		Solution
		Discussion
Chapter 10. TypeScript and React
	10.1 Writing Proxy Components
		Problem
		Solution
		Discussion
	10.2 Writing Controlled Components
		Problem
		Solution
		Discussion
	10.3 Typing Custom Hooks
		Problem
		Solution
		Discussion
	10.4 Typing Generic forwardRef Components
		Problem
		Solution
		Discussion
	10.5 Providing Types for the Context API
		Problem
		Solution
		Discussion
	10.6 Typing Higher-Order Components
		Problem
		Solution
		Discussion
	10.7 Typing Callbacks in React’s Synthetic Event System
		Problem
		Solution
		Discussion
	10.8 Typing Polymorphic Components
		Problem
		Solution
		Discussion
Chapter 11. Classes
	11.1 Choosing the Right Visibility Modifier
		Problem
		Solution
		Discussion
	11.2 Explicitly Defining Method Overrides
		Problem
		Solution
		Discussion
	11.3 Describing Constructors and Prototypes
		Problem
		Solution
		Discussion
	11.4 Using Generics in Classes
		Problem
		Solution
		Discussion
	11.5 Deciding When to Use Classes or Namespaces
		Problem
		Solution
		Discussion
	11.6 Writing Static Classes
		Problem
		Solution
		Discussion
	11.7 Working with Strict Property Initialization
		Problem
		Solution
		Discussion
	11.8 Working with this Types in Classes
		Problem
		Solution
		Discussion
	11.9 Writing Decorators
		Problem
		Solution
		Discussion
Chapter 12. Type Development Strategies
	12.1 Writing Low Maintenance Types
		Problem
		Solution
		Discussion
	12.2 Refining Types Step by Step
		Problem
		Solution
		Discussion
	12.3 Checking Contracts with satisfies
		Problem
		Solution
		Discussion
	12.4 Testing Complex Types
		Problem
		Solution
		Discussion
	12.5 Validating Data Types at Runtime with Zod
		Problem
		Solution
		Discussion
	12.6 Working Around Index Access Restrictions
		Problem
		Solution
		Discussion
	12.7 Deciding Whether to Use Function Overloads or Conditional Types
		Problem
		Solution
		Discussion
	12.8 Naming Generics
		Problem
		Solution
		Discussion
	12.9 Prototyping on the TypeScript Playground
		Problem
		Solution
		Discussion
	12.10 Providing Multiple Library Versions
		Problem
		Solution
		Discussion
	12.11 Knowing When to Stop
		Problem
		Solution
		Discussion
Index
About the Author