freeCodeCamp Challenge Guide: Understanding Undefined Value returned from a Function

Understanding Undefined Value returned from a Function


Hints

Hint 1

A function with no return statement, has an output of undefined. So, if you try to equal a varaible to the output of a function with no return statement, that variable will equal undefined.

Go ahead and define addFive() like so…

function addFive() {
  sum += 5;
}

As you can see, sum is added by 5 with no issues, but since there is no return statement, there is an undefined output.

var result = addFive(); // This is undefined
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