fn extern "c" printf(fmt: ptr[u8], ..) i32

type Box(value: int)
type Ref(box: &Box)
type Mut(box: &mut Box)
type Bag(a: Box, b: Box)

fn main() unit = {
    let mut box = Box(1)
    box.print() // Coerced to &Box
    box.set(42) // Coerced to &mut Box
    box.print() // box.value == 42

    let r = Ref(&box)
    print(r.box)

    let mut bag = Bag(Box(2), Box(3)).copy().copy()
    let ref-a = &mut bag.a
    let ref-b = &bag.b
    let ref-a = ref-a
    let ref-b = ref-b

    let ref-bag = &bag
    let a = &ref-bag.a
    let b = &ref-bag.b

    print(ref-a)
    print(ref-b)

    let mut box = Box(1)
    let mut rmut = Mut(&mut box)
    let m = &mut rmut.box
    rmut.box.value = 2
}

fn print(box: &Box) unit = {
    unsafe printf("Box(%d)\n".ptr, box.value)
}

fn set(box: &mut Box, value: int) unit =
    box.value = value

fn copy(bag: Bag) Bag = Bag(bag.a, bag.b)