anchor.diff:      _mBlob = blob;
     }
   
  -  Future<hetima.WriteResult> write(Object o, int start, [int length=null]) {
  +  Future<hetima.WriteResult> write(Object o, int start, [int length = null]) {
       if (o is List<int> && !(o is type.Uint8List)) {
         o = new type.Uint8List.fromList(o);
       }
  
positive.code:     _file.callMethod("remove", [
        () {
          ret.complete({});
        },
        (b) {
          ret.completeError(b);
  
negative.code:         //
          // seel
          {
            if (_writer["length"] < start) {
              //print("####[A] ${_writer["length"]} ${start}");
              List<int> d = new type.Uint8List.fromList(new List.filled(start - _writer["length"], 0));
              html.Blob b = new html.Blob([d, o]);
              _writer.callMethod("seek", [_writer["length"]]);
              _writer.callMethod("write", [b.slice(0, length + d.length)]);
            } else {
              // print("####[B] ${_writer["length"]} ${start} ${(o as type.Uint8List).length}");
              _writer.callMethod("seek", [start]);
              html.Blob b = new html.Blob([o]);
              _writer.callMethod("write", [b.slice(0, length)]);
            }
  