https://stackoverflow.com › questions › 33445415

Any time you are inside of a promise callback, you can use throw. However, if you're in any other asynchronous callback, you must use reject. For example, this won't trigger the catch: new Promise(function() {. setTimeout(function() {. throw 'or nah'; // return Promise.reject('or nah'); also won't work. }, 1000);

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

The Promise object represents the eventual completion (or failure) of an asynchronous operation and its resulting value. To learn about the way promises work and how you can use them, we advise you to read Using promises first.

https://stackoverflow.com › questions › 36652195

About promises - they automatically catch all uncaught errors inside the promise body. However, it's better to use reject callback instead of throwing an error.

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

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

A Promise is an object representing the eventual completion or failure of an asynchronous operation. Since most people are consumers of already-created promises, this guide will explain consumption of returned promises before explaining how to create them.

https://fr.javascript.info › promise-error-handling

Si nous utilisons throw à l’intérieur d’un gestionnaire `.then’, cela signifie une promesse rejetée, donc le contrôle saute au gestionnaire d’erreur le plus proche. En voici un exemple:

https://web.dev › articles › promises

The JavaScript promises API will treat anything with a then () method as promise-like (or thenable in promise-speak sigh), so if you use a library that returns a Q promise, that's fine, it'll play nice with the new JavaScript promises.

https://javascript.info › promise-error-handling

If we throw inside a .then handler, that means a rejected promise, so the control jumps to the nearest error handler. Here’s an example: new Promise((resolve, reject) => { resolve("ok"); }).then((result) => { throw new Error("Whoops!"); // rejects the promise }).catch(alert); // Error: Whoops!