fn main() unit = {
	println("Reference semantics:")
	ref-type()
	println()

	println("Value semantics (extern):")
	ext-type()
}

type Ref(field: int)

fn ref-type() unit = {
	let mut r = Ref(1)
	print(&r) // should be 1

	r.field = 2
	print(&r) // should be 2

	r.mutate()
	print(&r) // should be 3
}

fn mutate(r: &mut Ref) unit = {
	r.field = 3
}

fn print(r: &Ref) unit = {
	println("Ref(field: {r.field})")
}

type Ext extern(field: int)

fn ext-type() unit = {
	let mut ext = Ext(1)
	print(ext) // should be 1

	ext.field = 2
	print(ext) // should be 2

	ext.mutate()
	print(ext) // should still be 2
}

fn mutate(mut ext: Ext) unit = {
	ext.field = 3
}

fn print(ext: Ext) unit = {
	println("Ext(field: {ext.field})")
}