named.dart

class Points {
  final double x;
  final double y;
  
  //unnamed constructor
  Points(this.x, this.y);

  // Named constructor
  Points.origin(double x,double y)
      : x = x,
        y = y;
  
  // Named constructor
  Points.destination(double x,double y)
      : x = x,
        y = y;
}