static ItIt<ParsedWithTokens<S>> pwt_followingTokens(int minTokens, int maxTokens, ListAndIndex<S> tok) {
  int remaining = countRemainingTokens(tok);
  ret countIterator_inclusive(
    min(minTokens, remaining),
    min(maxTokens, remaining),
    n -> new ParsedWithTokens(joinSubList(tok.list, tok.idx, tok.idx+n*2-1)));
}