module main

@[heap]
interface IGameObject {
mut:
	name  string
	speed f32
	owner ?&IGameObject
	collision(mut o IGameObject)
}

@[heap]
struct GameObject implements IGameObject {
mut:
	name  string
	speed f32
	owner ?&IGameObject
}

fn (mut gameobject GameObject) collision(mut o IGameObject) {
	_ = o
	if gameobject != gameobject.owner {
		eprintln('Collision')
	}
}

fn main() {
	mut ship := &GameObject{
		name: 'ship'
	}
	mut rocket := &GameObject{
		name:  'rocket'
		owner: ship
	}
	rocket.collision(mut ship)
}