Javascript Array Map Promise All

To fetch an array of urls with promise.all with javascript, we call promise.all with an array of promises. Here, promise.all () method is the order of the maintained promises. (async () => { const items = [1, 2, 3] const vals = await promise.all (items.map (async (it) => it * 2)) console.log (vals) }) () to calls items.map with an async function as the callback.

Here the promise.all () method waits till all the promises resolve. Here, promise.all () method is the order of the maintained promises. This returned promise will resolve when all of the input's promises have resolved, or if the input iterable contains no promises.

Const texts = await promise.all ( urls.map (async (url) => { const resp = await fetch (url);

Think of looping as a way to progress from one element to another in a list, while still maintaining the order and position of each element. That's where promises.all () comes in. Here, promise.all () method is the order of the maintained promises. This returned promise will resolve when all of the input's promises have resolved, or if the input iterable contains no promises.