fixed.nim

type
  # ...
  Vector*[T] = object
    x*, y*: T

  Animatable* = ref object of RootObj

  Ball* = ref object of Animatable
    pos*: Vector[float]
    

method clone*(anim: Animatable): Animatable  {.base.} =
  raise
  
method badclone*(anim: Animatable): Animatable  {.base.} =
  raise
  
# this makes a bad (incomplete) copy
method badclone*(ball: Ball): Animatable =
  result.new
  result.deepCopy(ball)


# This works 
method clone*(ball: Ball): Animatable =
  var ball2 = new Ball
  ball2.deepCopy(ball)
  result = ball2
  
var
  ball = Ball(pos: Vector[float](x: 111, y: 999))
  goodball = ball.clone
  badball = ball.badclone

echo repr ball
echo repr goodball
echo repr badball