Function immutable_seq::finger_tree::cons_node

pub fn cons_node<T, M>(x0: Lazy<Node<T, M>>,
                       tree: Lazy<FingerTree<T, M>>)
                       -> Lazy<FingerTree<T, M>> where T: Measure<M> + 'static, M: Add<Output=M> + Zero + Copy + 'static