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

object.then(value => {
console.log(value);
};

Question 3

How do you handle the rejection of a Promise?

Answer 3

object.catch(error => {
console.log(error or error.message)
};

Question 4

What is “syntactic sugar”?

Answer 4

Syntax within a programming language that is designed to make things easier to read or to express?

Question 5

What is the typeof an ES6 class?

Answer 5

Function.

Question 6

Describe ES6 class syntax

Answer 6

Class keyword 
Name of class
Opening curly brace for class declaration
Constructor and Method definitions
Closing curly brace for class declaration

Question 7

What is “refactoring”?

Answer 7

Restructuring existing code without changing its external behavior.

Question 8

How are ES modules different from CommonJS modules?

Answer 8

They syntax is more compact
Their structure can be statically analyzed (for static checking, optimization, etc.).
Their support for cyclic dependencies is better than CommonJS’s.

Question 9

What kind of modules can Webpack support?

Answer 9

ECMASCript modules
CommonJS modules
AMD modules
Assets
WebAssembly modules

Question 10

Describe importing a module.

Answer 10

Import keyword

opening curly brace { if not a default import

Comma separated names of imports

Closing curly brace } if not a default import

From keyword

Directory string in parenthesis.

Question 11

Describe exporting a module.

Answer 11

Export keyword
If default add Default keyword. Only one per module

Either the variable name or the code block being exported.