pp(Point.new);              # => Point at 0,0
var p = Point(1, 2);        # create a point
pp(p);                      # => Point at 1,2
say p.x;                    # => 1
p.y += 1;                   # add one to y
pp(p);                      # => Point at 1,3

var c = Circle(4,5,6);      # create a circle
var d = c.clone;            # make a clone of it
d.r = 7.5;                  # and change the radius to 7.5
pp(c);                      # => Circle at 4,5 with radius 6
pp(d);                      # => Circle at 4,5 with radius 7.5