This repository is a personal “revision” / tutorial playground for TypeScript.
Each numbered folder (S1. …, S2. …, …) contains notes and small examples that illustrate a particular part of the language.
The final folder, S11. React and TS, adds a minimal React + Vite project to demonstrate how TypeScript is used in a real application.

Goal: have one place to review core TS concepts and experiment with code while slowly building up to a React + TS application.

S1. Basics/
S2. TS Compiler Journey/
S3. TS Folder Steup/
S4. Type inference VS Annotation/
S5. Type System & Narrowing/
   ├── any & unknown.md
   ├── implements.md
   ├── never.md
   ├── union.md
   ├── Type Narrowing.md
   ├── Type & Interface.md
   ├── Type Assertion.md
S6. Objects/
S7. Data Types/
   ├── Arrays.md
   ├── Enum.md
   ├── Tuples.md
S8. OOP/
S9. Interface & Generics/
   ├── Interface.md
   ├── generics.md
S10. Web Requests/
S11. React and TS/
   ├── src/            ← small Vite/React app
   ├── package.json
   ├── tsconfig*.json
   └── …others

Each .md file is self‑contained; read them in order or jump to the concept you want to refresh.

These are mostly Markdown notes and tiny *.ts snippets.
To compile the small project in S3. TS Folder Steup:

cd "S3. TS Folder Steup"
npm install          # installs TypeScript
npm run dev          # runs `npx tsc` per package.json
npm start            # node dist/index.js

The tsconfig in that folder (/src/index.ts) shows the basic rootDir/outDir setup used throughout the repo.

You can npx tsc -p <folder> from any other section to try out the code there, or open the Markdown files in your editor and copy snippets into a scratch file.

This is a tiny Vite‑powered React app demonstrating:

• function components with typed props,
• hooks (useState, useEffect, custom useFetch),
• generic interfaces, PropsWithChildren, etc.

To run it:

cd "S11. React and TS"
npm install
npm run dev         # starts Vite dev server
# open http://localhost:5173 in your browser
npm run build       # production build
npm run preview     # preview build locally

You can inspect src/ for examples of interfaces, generics, and a simple useFetch hook.

• S1 – Why TypeScript? basic syntax & annotations
• S2 – What happens inside the TS compiler
• S3 – Project setup, tsconfig, npm scripts
• S4 – Inference vs. annotation
• S5 – Type system & narrowing (any/unknown, unions, type guards, never, implements, type assertions, etc.)
• S6 – Objects, structural typing, utility types
• S7 – Data types (arrays, tuples, enums, readonly, union arrays)
• S8 – OOP (classes, modifiers, getters/setters, inheritance, abstract, composition)
• S9 – Interfaces & generics (generic functions, constraints, default params, interface merging/extends)
• S10 – Web requests (Axios vs fetch, .d.ts files, typing API responses)
• S11 – React + TS (components, hooks, props, project structure)

• All Markdown files include explanatory comments and examples; they’re meant to be read, edited, and executed in a small sandbox.
• The React project is intentionally minimal—feel free to fork it and extend it as you practice.
• This repo is not a production application; it’s a learning resource. Feel free to copy any sections into other projects.

Feel free to use and adapt the examples however you like.

Happy revising!
Mayank Bhai