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How promises perform asynchronous tasks?
I understand how callback works asynchronously, but I cannot understand how promise does it.
JASON LEE13,616 Points
If you understand how callback works asynchronously, then you can see when declaring a new
Promise, it accepts a parameter which is a callback function.
Promise uses a callback function, and callback function works asynchronously, therefore
Promise works asynchronously.
The callback function is the one that is passed two arguments (resolve and reject).
This is my understanding so someone feel free to correct me if I'm wrong.
EDIT: I am not sure whether or not callback functions by themselves are asynchronous (probably not?), but they are often seen in asynchronous operations due to the ordering in which it's executed. Also now I'm second guessing whether I used the proper terms: parameter vs argument, or vice-versa. Because if you can't distinguish parameter vs argument, esp. when working with callback/higher order functions, it's really easy to get lost. Someone please advise.