anchor.diff:  }
   
   void writeDateTime(ByteStream stream, DateTime value) {
  -  final int year = value.year;
  -  final int month = value.month;
  -  final int day = value.day;
  -  final int hour = value.hour;
  -  final int minute = value.minute;
  -  final int second = value.second;
  -  final int millisecond = value.millisecond;
  -  final int microsecond = value.microsecond;
  +  final year = value.year;
  +  final month = value.month;
  +  final day = value.day;
  +  final hour = value.hour;
  +  final minute = value.minute;
  +  final second = value.second;
  +  final millisecond = value.millisecond;
  +  final microsecond = value.microsecond;
     if ((hour == 0) &&
         (minute == 0) &&
         (second == 0) &&
  
positive.code: }
  
  void _writeDate(ByteStream stream, int year, int month, int day) {
    Uint8List date = new Uint8List(9);
    date[0] = TagDate;
    date[1] = 0x30 + (year ~/ 1000 % 10);
    date[2] = 0x30 + (year ~/ 100 % 10);
  
negative.code: 
  part of hprose.io;
  
  final _zero = BigInt.zero;
  final _nine = new BigInt.from(9);
  
  void writeInteger(ByteStream stream, int value) {
    if (0 <= value && value <= 9) {
  