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1. developer.mozilla.org › Global_Objects › PromisePromise - JavaScript | MDN - MDN Web Docs

   developer.mozilla.org › Global_Objects › Promise

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   Oct 7, 2024 · 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.

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

   www.w3schools.com › Js › js_promise

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   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. When a Promise object is "rejected", the result is an error object.

3. 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.

4. www.freecodecamp.org › news › javascript-promiseHow JavaScript Promises Work – Tutorial for Beginners

   www.freecodecamp.org › news › javascript-promise

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   Nov 29, 2023 · Basically, a Promise object represents a “pending state” in the most common sense: the promise will eventually be fulfilled at a later date. To give you an illustration, suppose you want to buy a new phone to replace your old phone, so you open a messaging app to contact a phone store.

5. 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”.

6. developer.mozilla.org › Asynchronous › PromisesHow to use promises - Learn web development | MDN - MDN Web Docs

   developer.mozilla.org › Asynchronous › Promises

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   Jul 25, 2024 · A promise is an object returned by an asynchronous function, which represents the current state of the operation. At the time the promise is returned to the caller, the operation often isn't finished, but the promise object provides methods to handle the eventual success or failure of the operation.

7. People also ask

   What is a promise in JavaScript?

   • Promises in JavaScript represent processes that are already happening, which can be chained with callback functions. If you are looking to lazily evaluate an expression, consider using a function with no arguments e.g. f = () => expression to create the lazily-evaluated expression, and f () to evaluate the expression immediately.

   Promise - JavaScript | MDN - MDN Web Docs

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

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   What are the properties of a promise object?

   • 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. When a Promise object is "rejected", the result is an error object. You cannot access the Promise properties state and result.

   JavaScript Promises - W3Schools

   www.w3schools.com/Js/js_promise.asp

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   What is the state of a promise object?

   • A promise object has a state that can be one of the following: In the beginning, the state of a promise is pending, indicating that the asynchronous operation is in progress. Depending on the result of the asynchronous operation, the state changes to either fulfilled or rejected.

   JavaScript Promises - JavaScript Tutorial

   www.javascripttutorial.net/es6/javascript-promises/

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   What happens when a promise object is created?

   • Once a new Promise object is created, its state is pending. If a promise reaches fulfilled or rejected state, it is resolved. Note that you will rarely create promise objects in practice. Instead, you will consume promises provided by libraries. To get the value of a promise when it’s fulfilled, you call the then() method of the promise object.

   JavaScript Promises - JavaScript Tutorial

   www.javascripttutorial.net/es6/javascript-promises/

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   How to create a new promise object in Java?

   • When creating a new Promise object, we need to pass a callback function that will be called immediately with two arguments: the resolve() and reject() functions. Depending on the result of the Promise, either the resolve() or the reject() function will be called to end the pending state.

   How JavaScript Promises Work – Tutorial for Beginners

   www.freecodecamp.org/news/javascript-promise-object-explained/

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   How do you use a const promise in JavaScript?

   • console.log(error); const promise = getUsers(); How it works. First, define the success variable and initialize its value to true. If the success is true, the promise in the getUsers() function is fulfilled with a user list. Otherwise, it is rejected with an error message. Second, define the onFulfilled and onRejected functions.

   JavaScript Promises - JavaScript Tutorial

   www.javascripttutorial.net/es6/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' },