TypeScript - lesson 2 | HackIndia Skills

TypeScript - lesson 2 | HackIndia Skills | HackIndia

Your to-do

Install TypeScript

Do each one yourself, then tap it to tick it off. The ticks are only a checklist for you: they are not marked or scored.

Open your project folder in VS Code or your terminal.
Run npm init -y if the project does not already have a package.json.
Install TypeScript as a development dependency.
Check that npx tsc works from the project.
Commit package.json and package-lock.json after install.

0 of 5 done

npm init -y
npm install --save-dev typescript
npx tsc --version

Example

Small tsconfig

Create tsconfig.json at the project root. This is a safe starting point for a small app.

It checks your source files, writes build output to dist, and avoids checking installed packages.

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "ES2020",
    "moduleResolution": "Bundler",
    "rootDir": "src",
    "outDir": "dist",
    "strict": true,
    "noEmitOnError": true,
    "skipLibCheck": true
  },
  "include": ["src"]
}

Example

Add scripts

Your README should later show the same commands you use locally. Add scripts now so type-checking is one command.

For a basic TypeScript project, typecheck checks only. build checks and writes JavaScript into dist.

{
  "scripts": {
    "typecheck": "tsc --noEmit",
    "build": "tsc"
  },
  "devDependencies": {
    "typescript": "^5.0.0"
  }
}

Your to-do

Do this now

Do each one yourself, then tap it to tick it off. The ticks are only a checklist for you: they are not marked or scored.

Install TypeScript as a dev dependency in your project.
Create tsconfig.json with src as input and dist as output.
Add typecheck and build scripts to package.json.
Create src if it does not exist, then place one app file there.
Run npm run typecheck and save the result for your final repo proof.

0 of 5 done

npm run typecheck
npm run build

Set up TypeScript cleanly

One clean rule

What setup means

Install TypeScript

Small tsconfig

Start with src

Add scripts

Avoid global installs

Do this now

Quick check