# Module type Flow.G_GOLDBERG

    module type G_GOLDBERG = sig .. end

Minimal graph signature for Goldberg. Sub-signature of `Sig.G`.

    type t

    module V: Sig.COMPARABLE

    module E: Sig.EDGE  with type vertex = V.t

    val nb_vertex : t -> int

    val iter_vertex : (V.t -> unit) -> t -> unit

    val iter_edges_e : (E.t -> unit) -> t -> unit

    val fold_succ_e : (E.t -> 'a -> 'a) -> t -> V.t -> 'a -> 'a

    val fold_pred_e : (E.t -> 'a -> 'a) -> t -> V.t -> 'a -> 'a