docs: static private int indexOfNthOccurrenceOfCharIn(String str, char ch, int n) {
          boolean inMiddleOfQuote = false;
          int index = -1, previousIndex = 0;
          for (int i=0; i < n; i++) {
              do {
                  index = str.indexOf(ch, index+1);
                  if (index < 0) {
                      return -1;
                  }
                  if (hasOddNumberOfSingleQuotes(str.substring(previousIndex, index))) {
                      inMiddleOfQuote = !inMiddleOfQuote;
                  }
                  previousIndex = index;
              } while (inMiddleOfQuote);
          }
          return index;
      }