CPLIB_GRAPH_REVERSE_EDGE = 1

proc reverse_edge(G: UnWeightedDirectedGraph): UnWeightedDirectedGraph {.
    ...raises: [], tags: [].}

proc reverse_edge(G: UnWeightedDirectedStaticGraph): UnWeightedDirectedStaticGraph {.
    ...raises: [], tags: [].}

proc reverse_edge[T](G: WeightedDirectedGraph[T]): WeightedDirectedGraph[T]

proc reverse_edge[T](G: WeightedDirectedStaticGraph[T]): WeightedDirectedStaticGraph[
    T]