test_operations.mx

    struct Node<T> {
        data: T,
        @mut next: Option[Node[T]]
    }

    struct LinkedList<T> {
        @mut head: Option[Node[T]>
    }

    fn new_list<T>() -> LinkedList<T> {
        LinkedList[T] { head: None }
    }

    fn push_front<T>(list: @mut LinkedList<T>, value: T) {
        let new_node = Node[T] {
            data: value,
            next: list.head
        };
        list.head = Some(new_node);
    }

    fn main() {
        let @mut list = new_list();
        push_front(@mut list, 42);
        push_front(@mut list, 43);
        
        # This should type check correctly
        if let Some(head) = list.head {
            assert(head.data == 43);
        }
    }