anchor.diff:      rcInteger:        aStream.Write(fInt);
       rcExtended:       aStream.Write(fExtn);
       rcBoolean:        aStream.Write(fBool);
  +  else
  +    raise Exception.Create('Unexpected type');
     end;
   end;
   
  
positive.code:       vtAnsiString:     fType := rcAnsiString;
        vtPWideChar,
        vtUnicodeString:  fType := rcUnicodeString;
      end;
    end;
  end;
  
negative.code:     fExtn: Extended;
      fBool: Boolean;
    public
      constructor Create(aVarRec: TVarRec); overload;
  
      procedure SetByVarRec(aValue: TVarRec);
  