LFZ ES6 Quiz

Question 1

What is a code block? What are some examples of a code block?

Answer 1

Anything between {}. An example would be the {} after an if expression

Question 2

What does block scope mean?

Answer 2

Anything inside of a code block

Question 3

What is the scope of a variable declared with const or let?

Answer 3

The code block it is declared in

Question 4

What is the difference between let and const?

Answer 4

you can redeclare let, but you cant redeclare const

Question 5

Why is it possible to .push() a new value into a const variable that points to an Array?

Answer 5

the values of the array are mutable

Question 6

What is the syntax for writing a template literal?

Answer 6

using the backtick `

Question 7

What is “string interpolation”?

Answer 7

string formatting

Question 8

What is destructuring, conceptually?

Answer 8

Taking properties from objects and assigning them to variables

Question 9

What is the syntax for Object destructuring?

Answer 9

const/let {property: variable name, etc} = object

Question 10

What is the syntax for Array destructuring?

Answer 10

const/let [variable name, etc] = array

Question 11

How can you tell the difference between destructuring and creating Object/Array literals?

Answer 11

objects have {} and arrays have []

Question 12

What is the syntax for defining an arrow function?

Answer 12

let/const verName = functionParameters => (return expression)

Question 13

When an arrow function’s body is left without curly braces, what changes in its functionality?

Answer 13

it will implicitly return with out curly braces

Question 14

What are the three states a Promise can be in?

Answer 14

pending, fulfilled, and rejected

Question 15

How do you handle the fulfillment of a Promise?

Answer 15

with the then method

Question 16

How do you handle the rejection of a Promise?

Answer 16

with the catch method

Question 17

What is “syntactic sugar”?

Answer 17

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

Question 18

What is the typeof an ES6 class?

Answer 18

Function

Question 19

Describe ES6 class syntax.

Answer 19

class className { constructor(propertyName) {property assignment} customMethodName(){Method function}}

Question 20

How are ES Modules different from CommonJS modules?

Answer 20

ES Modules use Import and export statements, while CommonJS uses require.

Question 21

What kind of modules can Webpack support?

Answer 21

ES6, CommonJS, AMD