https://stackoverflow.com › questions › 40735418

A Promise tells you that it will execute at some point in time, without telling you when. The then chain will execute whenever the Promise resolves. You can see that in more detail in returnPromise. Here we return a new Promise.

https://developer.mozilla.org › fr › docs › Web › JavaScript › Reference › Global_Objects › Promise

Renvoie un objet Promise qui est rompue avec la raison donnée. Promise.resolve(valeur) Renvoie un objet Promise qui est tenue (résolue) avec la valeur donnée.

https://stackoverflow.com › questions › 29516390

Return a value → PromiseB is resolved immediately, and the value is passed to the success handler of promiseB. Return a promise → When resolved, promiseB will be resolved. When rejected, promiseB will be rejected. The value passed to the promiseB's then handler will be the result of the promise.

https://developer.mozilla.org › en-US › docs › Web › JavaScript › Reference › Global_Objects › Promise

Learn how to use the Promise object to handle asynchronous operations in JavaScript. A Promise represents the eventual completion or failure of an operation and its resulting value.

https://developer.mozilla.org › en-US › docs › Web › JavaScript › Guide › Using_promises

Since most people are consumers of already-created promises, this guide will explain consumption of returned promises before explaining how to create them. Essentially, a promise is a returned object to which you attach callbacks, instead of passing callbacks into a function.

https://developer.mozilla.org › fr › docs › Web › JavaScript › Guide › Using_promises

Promise.resolve() et Promise.reject() sont des méthodes qui permettent de créer des promesses déjà tenues ou rompues. Promise.all() et Promise.race() sont deux outils de composition qui permettent de mener des opérations asynchrones en parallèle.

https://www.w3schools.com › Js › js_promise.asp

Here is how to use a Promise: myPromise.then ( function (value) { /* code if successful */ }, function (error) { /* code if some error */ } ); Promise.then () takes two arguments, a callback for success and another for failure. Both are optional, so you can add a callback for success or failure only.

https://javascript.info › promise-basics

The function delay(ms) should return a promise. That promise should resolve after ms milliseconds, so that we can add .then to it, like this: