Topkg_os.Dirval exists : Topkg_fpath.t -> bool Topkg_result.resultval must_exist : Topkg_fpath.t -> Topkg_fpath.t Topkg_result.resultval current : unit -> Topkg_fpath.t Topkg_result.resultval set_current : Topkg_fpath.t -> unit Topkg_result.resultval with_current : Topkg_fpath.t -> ('a -> 'b) -> 'a -> 'b Topkg_result.resultval contents : ?dotfiles:bool -> ?rel:bool -> Topkg_fpath.t -> Topkg_fpath.t list Topkg_result.result