palidrome checker

function palindrome(str) {
  var cleanUp = str.replace(/([^a-z0-9]+)/gi , '').toLowerCase();
  var og=str.replace(/([^a-z0-9]+)/gi , '').toLowerCase();
  var temp="";
  
  for (var i = cleanUp.length - 1; i >= 0; i--) {
        temp += cleanUp[i];
    }
  
  if(temp == og){
    return true;
  }
  return false;
}



palindrome("eye");