code: public static String stripInitialWhitespace(String s) {
          int i = 0;
  
          while ((i < s.length()) && charInString(s.charAt(i), whitespace)) i++;
          return s.substring(i);
          // return s.substring(i, s.length);
      }
docs: Removes initial(leading) whitespace characters from s.
  Member whitespace(see above) defines which characters are considered whitespace.