Callbacks vs. Promises vs. Async Await: A Step by Step Guide | by Anton Franzen | Feb, 2022

As a substitute of callback hell, we will chain guarantees in several methods, instance, if we want to make one other request as soon as our first request, has resolved we will do that:


Guarantees have one thing known as Promise.all which permits us to attend for any variety of guarantees to resolve, after which execute a code block. This may be very very helpful, for instance, if we’d have an array of requests we have to name and watch for all requests to complete, then we will do that in just a few strains of code like this:

So mainly what if we may write code that regarded sequential however really is absolutely promise-based? As we noticed with guarantees after it resolves we have to name .then() and it’s not actually sequential as we wish it.

Now, I didn’t convey up all the pieces there’s to this, really, there’s a lot I didn’t convey up, resembling methods to catch errors, optimization methods, and so forth. However I feel this offers you a primary grasp of what the distinction between the three is, how they work, how you should utilize them.

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