anchor.diff:  
     @override
     int get length {
  -    _length ??= bp._getUint64();
  +    _length ??= bp._getUint32();
       return _length;
     }
   
  
positive.code:     _prepare(8, 1 + values.length);
      Offset result = new Offset(_tail);
      int tail = _tail;
      _setUint64AtTail(_buf, tail, values.length);
      tail -= 8;
      for (double value in values) {
        _setFloat64AtTail(_buf, tail, value);
  
negative.code:   static void _setUint32AtTail(ByteData _buf, int tail, int x) {
      _buf.setUint32(_buf.lengthInBytes - tail, x, Endianness.LITTLE_ENDIAN);
    }
  }
  
  /**
  