anchor.diff:    
     List<XChartsDataSeries> get series => new List.from( this._allSeries ) ;
     List<XChartsDataSeries> get seriesEnabled => new List.from( this._allSeries.where( (s) => s.enabled ) ) ;
  +  CanvasElement get canvas => _canvas ; 
     
     void clearSeries() => _allSeries.clear() ;
     
  
positive.code:   }
    
    XChartsDataSeries clone(){
      XChartsDataSeries clone = new XChartsDataSeries(this.name, this.data);
      clone.color = this.color;
      clone.enabled = this.enabled;
      
  
negative.code:   Map<String, dynamic> _props = {} ;
    
    Map<String, dynamic> get properties => _props ;
    set properties(Map props) => _props = props ;
    
    NumericalList asNumericalListXValues() {
      return new NumericalList.fromList( getXValues() ) ;
  