import 'dart:math';
class Position {
int x;
int y;
double distanceTo(Position other) {
var dx = other.x - x;
var dy = other.y - y;
return sqrt(dx * dx + dy * dy);
}
}
class Square {
int width;
int height;
int get area => width * height;
}
// Classes can be mixed in using 'with'
class SquareView extends Square with Position {}
main() {
var origin = new Position()
..x = 0
..y = 0;
var square = new SquareView()
..x = 5
..y = 5
..width = 10
..height = 10;
print(square.distanceTo(origin));
print(square.area);
}
$ dart mixins.dart
7.0710678118654755
100