static IterableIterator<Matches> gJMatch(final S pat) {
  final L<S> log = gLog();
  
  ret new IterableIterator<Matches>() {
    int i = l(log);
    new Matches m;
    
    public bool hasNext() {
      while (--i >= 0 && !jmatch(pat, get(log, i), m));
      ret i >= 0;
    }
    
    public Matches next() {
      ret m;
    }
  };
}