anchor.diff:      return output;
     }
   
  -  KId xorToThe(int x, {KId output:null, bool repeat:false}) {
  +  KId xorToThe(int x, {KId output: null, bool repeat: false}) {
       if (output == null) {
         output = new KId.zeroClear();
       }
  
positive.code: import 'package:hetimacore/hetimacore.dart';
  import 'dart:typed_data';
  
  class KId implements Comparable<KId>{
    List<int> _values = null;
    List<int> get value => new List.from(_values);
    List<int> get rawvalue => _values;
  
negative.code:       int i = x ~/ 8;
        int v = x % 8;
        int d = 0;
        if (repeat) {
          for (int j = 0; j <= v; j++) {
            d |= (0x01 << j);
          }
        } else {
          d = (0x01 << v);
        }
        output._values[19 - i] = this._values[19 - i] ^ d;
        return output;
      }
    }
  