es6-const-let

Question 1

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

Answer 1

Code within two { }… for, while, if, etc

Question 2

What does block scope mean?

Answer 2

Variables only work within a specific code block.

Question 3

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

Answer 3

Let keywords are block-scoped. Const is read only block-scope variable.

Question 4

What is the difference between let and const?

Answer 4

Let can change, while const remains fixed. Const also needs to be initialized.

Question 5

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

Answer 5

Variable only holds a pointer to a memory… You can make modifications.

Question 6

How should you decide on which type of declaration to use?

Answer 6

Depending on if you want to change a value or a variable later or not. Always use const, and if you can’t, use let. Use let in a loop…. in an if statement, you can use let. Otherwise, always use const.