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JavaScript

Posted by Danny Percy
Danny Percy
3,719 Points

Why is conditional statement first?

Hey guys! I am curious why is conditional statement first inside function? I know that code won't run if return would be first, but still.. don't get it? Is there any rule which must go first inside functions? Thanks for your help! Best Regards, Danny

function getRandom(lower,upper){
  if (isNaN(lower) || isNaN(upper)){
    throw new Error ('Something is wrong!');
  }
  return Math.floor(Math.random() * (lower - upper + 1)) + lower;
}

console.log(getRandom(5,6));
console.log(getRandom('Nine',6));
console.log(getRandom(5,'Five'));

2 Answers

Joseph Wasden
Joseph Wasden
20,407 Points
Joseph Wasden
Joseph Wasden
20,407 Points

No rule about conditional statement ordering; they can appear in any order inside a function.

However, in the above code, the conditional is ordered first because it is validating the arguments passed into the function. If either argument is NAN (Not a Number), then the function will throw an error. The conditional appears first because it wants to validate the arguments first.

Danny Percy
Danny Percy
3,719 Points
Danny Percy
Danny Percy
3,719 Points

ahha! I got it! thanks for you help buddy! :)