type graph = G.ttype edge_label = G.E.labelval merge_edges_with_label : ?src:G.vertex -> ?dst:G.vertex -> ?label:edge_label -> graph -> edge_label -> graphMerge.Ptype graph = G.ttype edge_label = G.E.labelval merge_edges_with_label : ?src:G.vertex -> ?dst:G.vertex -> ?label:edge_label -> graph -> edge_label -> graph