Mastering JavaScript Promises

Promises help you write cleaner asynchronous code by representing a value that may be available now, later, or never.

Why Promises?

• Avoids callback hell
• Easier to read and maintain
• Works seamlessly with async/await

Basic Example

const fetchUser = () => {
  return fetch('/api/user')
    .then(res => res.json())
    .catch(err => console.error(err));
}

Chaining Promises

fetch('/api/user')
  .then(res => res.json())
  .then(user => fetch(`/api/posts?user=${user.id}`))
  .then(res => res.json())
  .then(posts => console.log(posts))
  .catch(err => console.error(err));

Key Takeaways

• Always return promises from .then()
• Use .catch() for error handling
• Prefer async/await for readability

Happy coding! 🚀