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1. developer.mozilla.org › en-US › docsPromise - JavaScript | MDN - MDN Web Docs

   developer.mozilla.org › en-US › docs

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   Oct 7, 2024 · A Promise is a proxy for a value not necessarily known when the promise is created. It allows you to associate handlers with an asynchronous action's eventual success value or failure reason.

2. www.w3schools.com › Js › js_promiseJavaScript Promises - W3Schools

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   A Promise is an object that links producing code and consuming code in JavaScript. Learn how to use Promise syntax, properties, methods and examples with W3Schools.

3. www.geeksforgeeks.org › javascript-promiseJavaScript Promise - GeeksforGeeks

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   Oct 9, 2024 · What is a Promise? A promise in JavaScript is like a container for a future value. It is a way of saying, “I don’t have this value right now, but I will have it later.” Imagine you order a book online. You don’t get the book right away, but the store promises to send it to you.

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4. javascript.info › promise-basicsPromise - The Modern JavaScript Tutorial

   javascript.info › promise-basics

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   Jun 23, 2024 · A promise is a special JavaScript object that links the “producing code” and the “consuming code” together. In terms of our analogy: this is the “subscription list”.

5. developer.mozilla.org › en-US › docsUsing promises - JavaScript | MDN - MDN Web Docs

   developer.mozilla.org › en-US › docs

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   Oct 7, 2024 · 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.

6. www.freecodecamp.org › news › guide-to-javascriptHow Promises Work in JavaScript – A Comprehensive Beginner's ...

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   Jun 13, 2023 · This article is an in-depth guide to promises in JavaScript. You are going to learn why JavaScript has promises, what a promise is, and how to work with it. You are also going to learn how to use async/await—a feature derived from promises—and what a job queue is. Here are the topics we will cover: Why should you care about promises?

7. People also ask

   What is a JavaScript promise object?

   • When the producing code obtains the result, it should call one of the two callbacks: A JavaScript Promise object can be: The Promise object supports two properties: state and result. While a Promise object is "pending" (working), the result is undefined. When a Promise object is "fulfilled", the result is a value.

   JavaScript Promises - W3Schools

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   What is a new promise in JavaScript?

   • The function passed to new Promise is called the executor. When new Promise is created, the executor runs automatically. It contains the producing code which should eventually produce the result. In terms of the analogy above: the executor is the “singer”. Its arguments resolve and reject are callbacks provided by JavaScript itself.

   Promise - The Modern JavaScript Tutorial

   javascript.info/promise-basics

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   How to demonstrate the use of promises in JavaScript?

   • To demonstrate the use of promises, we will use the callback examples from the previous chapter: ECMAScript 2015, also known as ES6, introduced the JavaScript Promise object. The following table defines the first browser version with full support for Promise objects:

   JavaScript Promises - W3Schools

   www.w3schools.com/Js/js_promise.asp

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   Are promises always part of JavaScript?

   • Promises were not always part of JavaScript. Callbacks worked together with asynchronous functions to produce desired results in the past. A callback is any function that is a parameter of an async function, which the async function invokes to complete its operation. To call an async function, you had to pass a callback as an argument like this:

   How Promises Work in JavaScript – A Comprehensive Beginner's Guide

   www.freecodecamp.org/news/guide-to-javascript-promises/

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   What is the difference between a fan and a promise in JavaScript?

   • That’s a “singer”. A “consuming code” that wants the result of the “producing code” once it’s ready. Many functions may need that result. These are the “fans”. A promise is a special JavaScript object that links the “producing code” and the “consuming code” together. In terms of our analogy: this is the “subscription list”.

   Promise - The Modern JavaScript Tutorial

   javascript.info/promise-basics

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   How do I create a promise in JavaScript?

   • To create a promise, you need to create an instance object using the Promise constructor function. The Promise constructor function takes in one parameter. That parameter is a function that defines when to resolve the new promise, and optionally when to reject it. For example, assume you want a promise to resolve after a timeout of two seconds.

   How Promises Work in JavaScript – A Comprehensive Beginner's Guide

   www.freecodecamp.org/news/guide-to-javascript-promises/

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8. www.javascripttutorial.net › es6 › javascript-promisesJavaScript Promises - JavaScript Tutorial

   www.javascripttutorial.net › es6 › javascript-promises

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   JavaScript Promises. Summary: in this tutorial, you will learn about JavaScript promises and how to use them effectively. Why JavaScript promises. The following example defines a function getUsers() that returns a list of user objects: function getUsers() { return [ { username: 'john', email: 'john@test.com' },