static boolean match_brackets(S pat, S s) {
  return match_brackets(pat, s, null);
}

static boolean match_brackets(S pat, S s, Matches matches) {
  if (pat == null || s == null) false;
  ret match3(pat, parse3_brackets(s), matches);
}
  
static boolean match_brackets(S pat, L<S> toks, Matches matches) {
  L<S> tokpat = parse3_brackets(pat);
  ret match3(tokpat,toks,matches);
}

static boolean match_brackets(L<S> tokpat, L<S> toks, Matches matches) {
  S[] m = match2(tokpat, toks);
  //print(structure(tokpat) + " on " + structure(toks) + " => " + structure(m));
  if (m == null) false;
  if (matches != null) matches.m = m; true;
}

Began life as a copy of #1001104