error[E0432]: unresolved import `graph::stable::StableGraph`
  --> src/visit.rs:27:5
   |
27 | use graph::stable::StableGraph;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ Could not find `stable` in `graph`

error[E0207]: the type parameter `N` is not constrained by the impl trait, self type, or predicates
  --> src/visit.rs:63:10
   |
63 | impl<'a, N, E: 'a, Ty, Ix> IntoNeighbors for &'a StableGraph<N, E, Ty, Ix>
   |          ^ unconstrained type parameter