ES6 Promises

The video tutorial introduces promises, a feature of the ES6 standard, as an alternative to callbacks for handling asynchronous operations. It explains how promises work, using a create post example to demonstrate their implementation. The tutorial covers error handling with promises using reject and catch methods. Finally, it introduces the Fetch API, which uses promises for making HTTP requests, as a modern alternative to Ajax and XHR.

What is a promise in JavaScript primarily used for?

• Managing memory allocation

• Handling synchronous operations

• Creating new variables

• Handling asynchronous operations

Which method is used to handle a resolved promise?

• .catch()

• .resolve()

• .finally()

• .then()

What are the two parameters passed to the function inside a promise?

• Accept and Decline

• Resolve and Reject

• Start and Stop

• Open and Close

In the context of promises, what is the purpose of the 'reject' function?

• To resolve the promise

• To handle successful operations

• To indicate an error occurred

• To pause the promise

How can you catch errors in a promise?

• Using .finally()

• Using .then()

• Using .resolve()

• Using .catch()

What will happen if a promise is rejected and there is no catch block?

• An uncaught error will occur

• The promise will resolve

• The promise will retry

• The error will be ignored

Why is understanding promises important before learning the Fetch API?

• Fetch API is deprecated

• Fetch API is unrelated to promises

• Fetch API returns a promise

• Fetch API does not use promises