es6

Question 1

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

Answer 1

In JavaScript, blocks are denoted by curly braces {} , for example the if else, for, do while, while, try catch and so on:

Question 2

What does block scope mean?

Answer 2

Variable definition is only valid within the scope of the code block it was declared in

Question 3

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

Answer 3

block scope

Question 4

What is the difference between let and const?

Answer 4

you can reassign the value for let, not const. Const is also a read only reference?

Question 5

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

Answer 5

because you are not reassigning the value of the array object?
You are adding to the array not reassigning the variable

Question 6

What is the syntax for defining an arrow function?

Answer 6

(parameters) => code block

() not needed with one parameter
() are needed with no parameter

{} needed for more than one line of code

Question 7

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

Answer 7

You don’t get a return statement

Question 8

How is the value of this determined within an arrow function?

Answer 8

when it is defined not when its called, that’s regular functions

Question 9

if arrow left without curly braces

Answer 9

without curly braces, is implicit return