docs: static Matcher sequenceWithStuffAfterEndIsFalse(Matcher matcher) {
      if (matcher instanceof SeqMatcher) {
        boolean end = false;
        for (Matcher m : matcher.<SeqMatcher>as().matchers()) {
          if (m instanceof EndMatcher) {
            end = true;
          } else if (end && !m.alwaysMatches()) {
            return FalseMatcher.INSTANCE;
          }
        }
      }
      return matcher;
    }