public static final <T> Stream<T> diGraph(T root, Function<? super T, ? extends Stream<T>> edges)
    {
        return DiGraphIterator.stream(root, edges);
    }
public static final < T > Stream < T > diGraph ( T root , Function < ? super T , ? extends Stream < T > > edges ) { return DiGraphIterator . stream ( root , edges ) ; }
Returns stream for graph nodes starting with root. Function edges returns
stream for each node containing nodes edges.
@param <T>
@param root
@param edges
@return