Install the latest version of Node.js and npm. Verify if successful installed:
node -v
npm -v
Initialise a Node.js project and install Typescript:
mkdir my-awesome-project
cd my-awesome-project
yarn init -y
yarn add -D ts-node typescript @types/node
Add the following in package.json, using which you quickly execute a Typescript file.
"scripts": {
"start": "tsc index.ts; node index.js"
},
Create a Typescript source-code file named index.ts and add the following example code:
function findDuplicates(numberList): Set<number> {
const result = new Set<number>();
const hashSet = new Set<number>();
numberList.forEach((item) => {
if (hashSet.has(item)) {
result.add(item);
} else {
hashSet.add(item);
}
});
return result;
}
const testSet = [3, 4, 5, 1, 4, 5, 8, 4, 6];
console.log(findDuplicates(testSet));
Configure ESLint and Prettier
yarn add eslint @typescript-eslint/eslint-plugin @typescript-eslint/parser --dev
Create .eslintrc
{
"parser": "@typescript-eslint/parser",
"extends": ["plugin:@typescript-eslint/recommended"],
"parserOptions": { "ecmaVersion": 2018, "sourceType": "module" },
"rules": {}
}
Install the ESLint and Prettier plugin in VS-Code. After that, open user settings of VSCode and add the following config:
// Set the default
"editor.formatOnSave": true,
// Enable per-language
"[javascript]": {
"editor.formatOnSave": true,
},Visual studio code setting
That’s it 🎉 Start coding!