TypeScript Best Practices for Modern Development

TypeScript has become an essential tool for modern JavaScript development. Here are some best practices that will help you write better, more maintainable code.

1. Use Strict Type Checking

Always enable strict mode in your tsconfig.json:

{
  "compilerOptions": {
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true
  }
}

2. Leverage Union Types

Union types are powerful for handling multiple possible types:

type Status = 'loading' | 'success' | 'error'
type ID = string | number

function handleStatus(status: Status) {
  switch (status) {
    case 'loading':
      return 'Loading...'
    case 'success':
      return 'Success!'
    case 'error':
      return 'Error occurred'
  }
}

3. Use Generics for Reusability

Generics make your code more flexible and reusable:

interface ApiResponse<T> {
  data: T
  status: number
  message: string
}

function fetchData<T>(url: string): Promise<ApiResponse<T>> {
  return fetch(url).then(res => res.json())
}

4. Prefer Type Assertions Over Any

When you need to work with dynamic content, use type assertions:

// Bad
const user = data as any

// Good
interface User {
  id: number
  name: string
}
const user = data as User

Conclusion

Following these TypeScript best practices will help you write more robust and maintainable code. Remember to always prioritize type safety and readability.