type edgeinfo = {write : bool;read : bool;
}type error = | NodeAlreadyPresent of node
val string_of_error : error -> stringtype adjust = string * stringval default_filename : stringval create : unit -> graphval create_initial_hierarchy : graph -> unitval remove_empty_nodes : graph -> node list -> unitval shortname_of_node : node -> stringval gensym : string -> stringval iter_nodes : (node -> unit) -> graph -> unitval nb_nodes : graph -> intval nb_use_edges : graph -> intval string_of_node : node -> stringval display_with_gv : graph -> unit