groupBy

A better function to group arrays of objects by a key. Simple, type-safe, and zero dependencies.

🚀 Features

• ✨ Type-safe - Full TypeScript support with generics
• 🪶 Lightweight - Zero dependencies
• 🎯 Simple API - Easy to use, intuitive interface
• 🔧 Flexible - Support for nested keys and custom key functions
• 📦 Tree-shakeable - ESM support for optimal bundle size

📦 Installation

npm install group-by

or

yarn add group-by

🔨 Usage

Basic Usage

import { groupBy } from 'group-by';

const users = [
  { name: 'Alice', role: 'admin' },
  { name: 'Bob', role: 'user' },
  { name: 'Charlie', role: 'admin' }
];

const grouped = groupBy(users, 'role');
// Result:
// Map {
//   admin => [
//     { name: 'Alice', role: 'admin' },
//     { name: 'Charlie', role: 'admin' }
//   ],
//   user => [
//     { name: 'Bob', role: 'user' }
//   ]
// }

With Nested Keys

const products = [
  { name: 'Laptop', category: { type: 'electronics' } },
  { name: 'Phone', category: { type: 'electronics' } },
  { name: 'Desk', category: { type: 'furniture' } }
];

const grouped = groupBy(products, 'category.type');
// Result:
// Map {
//   electronics => [
//     { name: 'Laptop', category: { type: 'electronics' } },
//     { name: 'Phone', category: { type: 'electronics' } }
//   ],
//   furniture => [
//     { name: 'Desk', category: { type: 'furniture' } }
//   ]
// }

With Custom Key Function

const numbers = [1, 2, 3, 4, 5, 6];

const grouped = groupBy(numbers, (n) => n % 2 === 0 ? 'even' : 'odd');
// Result:
// {
//   odd: [1, 3, 5],
//   even: [2, 4, 6]
// }

🏗️ Development

# Install dependencies
yarn install

# Run in development mode
yarn dev

# Build the package
yarn build

# Run tests
yarn test

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

📄 License

This project is licensed under the ISC License - see the LICENSE file for details.

👤 Author

andreyalth

Made with ❤️ using TypeScript