JavaScript Concurrency: Omitting Promise Values

Welcome to the Omitting Promise Values lesson!

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If a JavaScript function is written using { curly braces }, but doesn't have an explicit return statement, then it will always return undefined.

function noReturn() {
}
noReturn();

undefined

The same goes for Promise.resolve: if we omit its argument, the promise will fulfill, but it will contain undefined.
>
Promise.resolve();
Async Result:
Asynchronous ResultThis result will wait up to 3000ms for a response from the code before returning.
{fulfilled: undefined}
This applies to our then callbacks as well. If we don't return a value explicitly, the promise will fulfill with undefined.
>
Promise.resolve(5)
.then(function(n) {
/* Do nothing. */
});
Async Result:
Asynchronous ResultThis result will wait up to 3000ms for a response from the code before returning.
{fulfilled: undefined}
Here's a code problem:
This promise is fulfilled with the value 5. Attach a then callback that doesn't return anything. That will create a promise that fulfills with undefined.
Promise.resolve(5)
.then(() => {
});
Async Result:
Asynchronous ResultThis result will wait up to 3000ms for a response from the code before returning.
Goal:
{fulfilled: undefined}
Yours:
{fulfilled: undefined}
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