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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Random Number Challenge, Part II Solution

Joel Pendleton
Joel Pendleton
19,230 Points
Posted by Joel Pendleton
Joel Pendleton
19,230 Points

My Response 

function randomNum(num1, num2) {
  if (isNaN(num1) || isNaN(num2)) {
    throw new Error('Please enter a number.');
  } else {
    return Math.floor(Math.random() * (num1 - num2 + 1)) + num2;  
  }
}

The else conditional statement ensures that a random number will only be generated if both num1 and num2 are numbers. There's no need for this else statement if an error is thrown before it. This is because, the program wouldn't run the following lines of code after the error (because the program ends). However, you should add the else condition if there is no error message being thrown to ensure that your random number generator is only run under your wanted conditions - num1 and num2 being numbers and not strings.

1 Answer

Iain Simmons
MOD
Iain Simmons
Treehouse Moderator 32,305 Points
Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

You're correct, the else isn't needed, but you've also done something that many programmers recommend, which is to be explicit. That is, making it clear that the return statement should only be run if the parameters are integers.