TypeScript Knowledge Bank (WIP)

This repository is a collection of TypeScript examples and knowledge, ranging from fundamental topics to advanced techniques. It is intended to serve as a comprehensive resource for developers looking to learn and master TypeScript, as well as a showcase of advanced TypeScript concepts.

This is not about how TypeScript or JavaScript works under the hood, its all about types and the typelevel.

Structure

The repository is organized into folders by topic, with each folder containing TypeScript files that demonstrate specific concepts. Below are the key sections:

1. Essential Types

Covers basic TypeScript types and concepts:

• 1-1 Basic Types: Demonstrates primitive types like string, number, boolean.
• 1-2 Interfaces and Types: Differences between interface and type.
• 1-3 Type Annotations: How to explicitly annotate types in functions and variables.
• 1-4 Literals: Usage of literal types.
• 1-5 Utility Types: Key TypeScript utility types like Partial, Readonly, Record.

2. Type Manipulation

Advanced type operations:

• 2-1 Generics: Types that take parameters.
• 2-2 Keyof Type Operator: Creating new types using the keyof operator.
• 2-3 Typeof Type Operator: Creating new types based on the value using the typeof operator.
• 2-4 Indexed Access Types: Accessing types using Type['property'].
• 2-5 Conditional Types: Types that behave like conditional logic.
• 2-6 Mapped Types: Transforming types using mapped type patterns.
• 2-7 Template Literal Types: Constructing types using template literals.

3. Functional Programming

TypeScript examples focused on functional programming techniques:

• 3-1 Option Types: Creating Some and None types for safer null checks.
• 3-2 Pipes: Function composition using pipes.
• 3-3 Partial Application: How to partially apply arguments to functions.
• 3-4 Currying: Breaking down functions into unary versions.
• 3-5 Overloading: Function overloading for different input types.

4. Classes and OOP

TypeScript class examples and object-oriented programming patterns:

• 4-1 Map: Demonstrating mapping patterns with classes.
• 4-2 Factory: Implementing the factory pattern with TypeScript classes.
• 4-3 Zod validation: Schema validations with ZOD.

5. Advanced Topics

In-depth TypeScript features:

• 5-1 Branded Types: Using branded types to prevent accidental type misuse.
• 5-2 Type-Safe Assertions: Creating assertions and type guards.

Running Examples

To install the dependencies, run the following command:

npm install

Each folder contains runnable TypeScript files. You can run a specific example using npm scripts. For example, to run the example from 1-1-basic-types, use the following command:

npm run 1-1

You can find the specific commands for each folder under the scripts section in package.json. Adjust the folder names accordingly for each example you'd like to run.

Contributing

Contributions are welcome! If you'd like to contribute to this project, feel free to:

• Open an issue: If you have any suggestions, bugs, or questions, open an issue.
• Submit a pull request (PR): If you have code improvements or new examples, feel free to fork the repository, make your changes, and submit a PR.

All contributions are appreciated, and together we can improve this knowledge bank for the TypeScript community.