Roman Numeral Converter arr.indexOf is not a function!?

JavaScript
1

First off, I don’t want you to help me solve this puzzle. Please understand that I know this code is really bad and I suspect that this does not lead to a solution let alone a good solution.

PLEASE DO NOT HELP ME SOLVE THE CHALLENGE

I tried converting an array of strings to an array of numbers using Number().

. For some reason when I do this FCC claims that arr.indexOf is not a function. What is this madness and why does it occur.

arr.indexOf is in the function assigned to arabicToRomanNumerals. I have left the comment “why?” above the line of code this is written in. Any advice on how to debug this in the future would be greatly appreciated.

Side note: What happened to the chatrooms we used to have?

My code so far

function convertToRoman(num) {
  
  // roman numerals go 3 up and one down
  var romanNumerals = ["M","D","C","L","X","V","I"];
  var arabicNumerals = [9,8,7,6,5,4,3,2,1,0];
  var numArr = Number(String(num).split(""));
  var fourLong = function(arr){
    if (arr.length < 4){
      arr.splice(0,0,0);
      fourLong(arr);
  }};
  fourLong(numArr);
  var arabicToRomanNumerals = function(arr, num){
    //why?
    if(arr.indexOf(num) === 0){
      return arr[0] * "M";
    } 
  };
  
  num = arabicToRomanNumerals(numArr, numArr[0]);
   
  return numArr;
}

convertToRoman(1000);

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Link to the challenge:

3

Thanks! I haven’t written any javascript for a while. I totally forgot about NaN