anchor.diff:      borderData ??= FlBorderData();
     }
   
  -  /// this function is used for animate between current and target data,
  -  /// used in the [BaseChartDataTween]
     BaseChartData lerp(BaseChartData a, BaseChartData b, double t);
   }
   
  -/***** BorderData *****/
  -
  -/// Border Data that contains
  -/// used the [Border] class to draw each side of border.
  +/// Holds data to drawing border around the chart.
   class FlBorderData {
     final bool show;
     Border border;
   
  +  /// [show] Determines showing or hiding border around the chart.
  +  /// [border] Determines the visual look of 4 borders, see [Border].
     FlBorderData({
       this.show = true,
       this.border,
  
positive.code:   final double interval;
    final double rotateAngle;
  
    const SideTitles({
      this.showTitles = false,
      this.getTitles = defaultGetTitle,
  
negative.code:   }
  }
  
  /// It gives you the axis value and gets a String value based on it.
  typedef GetTitleFunction = String Function(double value);
  
  /// The default [SideTitles.getTitles] function.
  ///
  /// It maps the axis number to a string and returns it.
  String defaultGetTitle(double value) {
    return '$value';
  }
  
  /// This class holds the touch response details.
  ///
  /// Specific touch details should be hold on the concrete child classes.
  class BaseTouchResponse {
    final FlTouchInput touchInput;
  
  