code: private static String stripOuterBrackets(String s) {
          try {
              if (S.isEmpty(s))
                  return s;
              if (R_.search(s)) {
                  // strip out the outer brackets
                  s = R_.stringMatched();
                  s = s.substring(1);
                  s = s.substring(0, s.length() - 1);
              }
          } catch (RuntimeException re) {
              // this unfortunately happens - so at least make it debuggable
              throw re;
          }
    
          return s;
      }
docs: strip the outer brackets of the given string s
  
  @param s
  @return - the stripped string