static S format3(S pat, O... args) {
    if (args.length == 0) return pat;
    
    L<S> tok = javaTokPlusPeriod(pat);
    int argidx = 0;
    for (int i = 1; i < tok.size(); i += 2)
      if (tok.get(i).equals("*"))
        tok.set(i, format3_formatArg(argidx < args.length ? args[argidx++] : "null"));
    return join(tok);
  }
  
  static S format3_formatArg(O arg) {
    if (arg == null) return "null";
    if (arg instanceof String) {
      S s = (S) arg;
      ret isIdentifier(s) || isNonNegativeInteger(s) ? s : quote(s);
    }
    if (arg instanceof Integer || arg instanceof Long) ret String.valueOf(arg);
    return quote(structure(arg));
  }