type FixedVec<T: Type, static N: usize> {
    len: usize = 0,
    items: [N]T,
    fn init(items: [N]T) -> Self {
        return FixedVec { items: items }
    }
    fn push(self: mutref<Self>, value: T) -> Void raises [Full] {
        if self.len == N {
            raise Full
        }
        self.items[self.len] = value
        self.len = self.len + 1
    }
    fn get(self: ref<Self>, index: usize) -> Maybe<T> {
        return std.mem.get(self.items, index)
    }
}

pub fn main(world: World) -> Void raises {
    var vec: FixedVec<u8, 4> = FixedVec.init<u8, 4>([0, 0, 0, 0])
    check vec.push(42)
    let first: Maybe<u8> = vec.get(0)
    if first.has && first.value == 42 {
        check world.out.write("constructors defaults ok\n")
    }
}