ation. At the time the promise is returned to the caller, the operation often isn't finished, but the promise object provides methods to handle the eventual success or failure of the operation.
A promise is an object returned by an asynchronous function, which represents the current state of the operation
then() itself returns a promise
Inside an async function, you can use the await keyword before a call to a function that returns a promise. This makes the code wait at that point until the promise is settled, at which point the fulfilled value of the promise is treated as a return value, or the rejected value is thrown
If you add catch() to the end of a promise chain, then it will be called when any of the asynchronous function calls fails.
First, a promise can be in one of three states:
async and await
Adding async at the start of a function makes it an async function
Inside an async function, you can use the await keyword before a call to a function that returns a promise.
completed with the result of the function passed to it
what "succeeded" or "failed" means here is up to the API
pending: the promise has been created, and the asynchronous function it's associated with has not succeeded or failed yet
fulfilled: the asynchronous function has succeeded. When a promise is fulfilled, its then() handler is called
rejected: the asynchronous function has failed. When a promise is rejected, its catch() handler is called
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