fn d(n int) f64 {
	return f64(n)
}

fn e(n int) {}

fn f(n int) ?f64 {
	return f64(n)
}

fn g(n int) ? {}

fn main() {
	tg := [
		spawn d(0),
		spawn d(1),
	]
	r := tg.wait()?
	println(r)
	s := tg[0].wait() or { panic('problem') }
	println(s)
	tg2 := [
		spawn e(0),
		spawn e(1),
	]
	tg2.wait() or { panic('problem') }
	tg2[0].wait()?
	tg3 := [
		spawn f(0),
		spawn f(1),
	]
	tg3.wait() or { panic('problem') }
	for t in tg3 {
		a := t.wait()
		println(a)
	}
	for i, _ in tg3 {
		a := tg3[i].wait()
		println(a)
	}
	tg4 := [
		spawn g(0),
		spawn g(1),
	]
	tg4.wait()
	tg4[0].wait()
	spawn g(3) or { panic('problem') }
}