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7,823 Points

Can someone explain to why isNaN isnt working?

When I type a string in, NaN comes up instead of the new error message

function randomNumber(top, lower) { return Math.floor(Math.random() * (top - lower)) + 1;
if (isNaN(top) || isNan(lower) ) { throw new Error("input is NOT a number");}}

1 Answer

Your function is returning a value first and ignores the conditions after. All you need to do is change the order to First, check if the arguments isNan() if so, throw the error else return the value.

function randomNumber(top, lower) {
  if (isNaN(top) || isNaN(lower)) {
    throw new Error("input is NOT a number");
  return Math.floor(Math.random() * (top - lower)) + 1;