srecord TimestampRange(Timestamp start, Timestamp end) is Comparable<TimestampRange> {
  *(long start, long end) {
    this(Timestamp(start), Timestamp(end));
  }
  
  Timestamp start aka startTime() { ret start; }
  Timestamp end aka endTime() { ret end; }
  
  selfType start aka startTime(Timestamp start) { this.start = start; this; }
  selfType end aka endTime(Timestamp end) { this.end = end; this; }
  
  bool complete() { ret start != null && end != null; }
  
  Duration duration() { ret !complete() ? null : end.minusAsDuration(start); }
  
  long length() { ret !complete() ? 0 : end.unixDate()-start.unixDate(); }
  
  toString { ret start + " to " + end; }
  
  public int compareTo(TimestampRange r) {
    ret cmp(start, r.start);
  }
  
  L<Timestamp> toList() { ret ll(start, end); }
}