ES6

Question 1

What are the three states a Promise can be in?

Answer 1

• pending: initial state, neither fulfilled nor rejected.
• fulfilled: meaning that the operation was completed successfully.
• rejected: meaning that the operation failed.

Question 2

How do you handle the fulfillment of a Promise?

Answer 2

Use then( ) method

Question 3

How do you handle the rejection of a Promise?

Answer 3

Use then( ) method or catch( ) method

Question 4

What is “syntactic sugar”?

Answer 4

Is syntax within a programming language that is designed to make things easier to read or to express.

It makes the language “sweeter” for human use: things can be expressed more clearly, more concisely, or in an alternative style that some may prefer.

Question 5

What is thetypeofan ‘ES6 class’?

Answer 5

The class declaration is just syntactic sugar of the constructor function, therefore, the result of the ‘typeof’ operator of ES6 class is function.

Question 6

Describe ES6 class syntax.

Answer 6

Class keyword followed by curly braces for the class declaration

Question 7

What is “refactoring”?

Answer 7

Code refactoring is the process of restructuring existing computer code—changing the factoring—without changing its external behavior; preserve functionality

Question 8

What doesfetch()return?

Answer 8

fetch()takes one argument — the path to the resource you want to fetch — and returns a promise containing aResponseobject.

Question 9

What is the default request method used byfetch()?

Answer 9

Get

Question 10

How do you specify the request method (GET,POST, etc.) when callingfetch?

Answer 10

By having a second parameter as an object containing the method request)