Module type Contraction.G

module type G = sig .. end

type t 

module V: Sig.COMPARABLE 

type vertex = V.t 

module E: Sig.EDGE  with type vertex = vertex

type edge = E.t 

val empty : t

val add_edge_e : t -> edge -> t

val fold_edges_e : (edge -> 'a -> 'a) -> t -> 'a -> 'a

val fold_vertex : (vertex -> 'a -> 'a) -> t -> 'a -> 'a