Javascript
JavaScript Fundamentals -- Variables and Scope

Variables and Scope Exercise

Outline

There are 5 parts of the exercise for this section. Fork this StackBlitz project to do the exercise.

Global Scope

Create a variable with global scope, and then print it to the console by using it inside a Function

Function Scope

Create a function, and then create a variable inside that function. Print the variable to the console:

  1. inside the function (both before and after the declaration)
  2. outside the function to see the difference

Block Scope

Create a function, and then create a variable inside an if statement in that function.

Print the variable to the console inside the block and outside the block to see the difference

Note: StackBlitz may hide the error from you; you can look in the page's developer tools to see the answer, or copy this section to an HTML page

var, let, const

Declare a variable with each of the above keywords, two for const (one that has a number, string, or boolean and one object or array)

Try to alter the value of each variable and see what happens in each scenario

On the object or array, try adding to the array or altering an attribute on the object as well as reassigning the value

Value vs. Reference

Declare a variable with a value of a number, string, or boolean, then copy it to another Variable

Log both variables, then change the value of one and log them again

Declare a variable with a value of an object or an array, then copy it to another Variable

Log both variables, then change the value of an attribute on one object or add an item to one array and log them again

 

I finished! On to the next chapter