Question 1

How do I convert a callback function to use Promises?

Accepted Answer

Use the new Promise() constructor or a promisify utility like Bluebird's Promise.promisify(), as shown in the guide with the loadImage example. This wraps error-first callbacks into promise-based APIs.

Question 2

What's the difference between Promise.all() and chaining .then()?

Accepted Answer

Promise.all() runs multiple promises in parallel and resolves when all complete, while chaining .then() executes sequentially. The guide illustrates this with image loading for parallel vs. series tasks.

Question 3

Why are errors in my Promise chain sometimes not caught?

Accepted Answer

Errors might be swallowed due to missing .catch() or implicit catch issues with throw; the guide explains error propagation and recommends explicit error handling to avoid debugging headaches.

Question 4

Promises vs async/await: which should I learn first?

Accepted Answer

Start with Promises to understand async fundamentals, as async/await builds on them. This guide covers Promises thoroughly but doesn't delve into async/await, which is now standard in modern JS.

Question 5

Is Bluebird still necessary for Promise development?

Accepted Answer

With native Promise support widespread, Bluebird is often redundant; the guide uses it for enhanced error handling but notes ES2015 alternatives like es6-promise for polyfills.

Question 6

How do I handle multiple async operations without callback hell?

Accepted Answer

Use Promise chaining for sequence and Promise.all() for parallelism, as demonstrated with image arrays. This avoids nested callbacks and improves code readability.

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