Explain the role of the Promise.resolve and Promise.reject methods.

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Aryan Kumar · Answer

The Promise.resolve and Promise.reject methods in JavaScript are used to create and return Promise objects with specified resolved values or rejected reasons, respectively. They play a crucial role in working with Promises and asynchronous operations. Here's an explanation of their roles:
Promise.resolve:
Role: Promise.resolve is used to create a Promise that is resolved with a specified value.Usage: You can use it when you want to return a Promise that immediately resolves with a specific value, typically when you want to represent a successful asynchronous operation.
Example:
const resolvedPromise = Promise.resolve(42);
resolvedPromise.then((result) => {
 console.log(result); // Outputs: 42
});
and 
Use Cases:
Converting non-Promise values into Promises, which is useful for standardizing asynchronous interfaces.Simplifying asynchronous control flow by providing a Promise immediately.
Promise.reject:
Role: Promise.reject is used to create a Promise that is rejected with a specified reason (an error or an error message).
Usage: You can use it when you want to return a Promise that immediately rejects, typically when you want to represent a failed asynchronous operation.
Example:
const rejectedPromise = Promise.reject(new Error('Something went wrong'));
rejectedPromise.catch((error) => {
 console.error(error.message); // Outputs: Something went wrong
});
Use Cases:
Explicitly signaling failure in asynchronous operations.Handling and propagating errors in Promise chains.
Both Promise.resolve and Promise.reject are useful for managing the flow of asynchronous code, allowing you to handle success and error cases explicitly. They help in creating Promise instances with known outcomes, making your asynchronous code more predictable and easier to reason about.

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Explain the role of the Promise.resolve and Promise.reject methods.

Revati S Misra

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