Function dfs_visitor

fn dfs_visitor<G, F, C>(
    graph: G,
    u: G::NodeId,
    visitor: &mut F,
    discovered: &mut G::Map,
    finished: &mut G::Map,
    time: &mut Time,
) -> C
where
    G: IntoNeighbors + Visitable,
    F: FnMut(DfsEvent<G::NodeId>) -> C,
    C: ControlFlow,