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Promises
1. Explain the concept of 'callback hell' and how to mitigate it.
Level: Expert | Frequency: High
2. What is a Promise in JavaScript?
Level: Expert | Frequency: High
3. Explain the three states of a Promise.
Level: Expert | Frequency: High
4. How do you create a new Promise in JavaScript?
Level: Expert | Frequency: High
5. What is the purpose of `Promise.resolve()` and `Promise.reject()`?
Level: Expert | Frequency: High
6. How do you handle the result of a Promise?
Level: Expert | Frequency: High
7. What is Promise chaining?
Level: Expert | Frequency: High
8. How do you handle errors in a chain of Promises?
Level: Expert | Frequency: High
9. What is the purpose of `Promise.all()` and `Promise.race()`?
Level: Expert | Frequency: High
10. How can you handle multiple Promises concurrently without using `Promise.all()`?
Level: Expert | Frequency: High
11. What is the purpose of the `async` and `await` keyword in JavaScript??
Level: Expert | Frequency: High
12. How do you handle errors when using `async/await`?
Level: Expert | Frequency: High
13. Do all `async` functions return Promises? Why or why not?
Level: Expert | Frequency: High
14. How does `Promise.finally()` work?
Level: Expert | Frequency: High
15. How do you convert a callback-based function into a Promise-based function?
Level: Expert | Frequency: High
16. What is the purpose of `Promise.promisify()`?
Level: Expert | Frequency: High
17. How can you create a custom Promise with timeout functionality?
Level: Expert | Frequency: High
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