Graph.Merge
Provides functions to extend any module satisfying one of the signatures Sig.P, Sig.I and Builder.S .
module type S = sig ... end
module B (X : Builder.S) : S with type graph = X.G.t and type vertex := X.G.vertex and type edge := X.G.edge and type edge_label = X.G.E.label
Extension for the module X
.