val get_exn : t ‑> string ‑> string option Lwt.t
val set_exn : t ‑> string ‑> string ‑> unit Lwt.t
val remove : t ‑> string ‑> unit Lwt.t
default ?dir ()
creates a new default storage (one file per pair)
dir
is not set, then the current directory is used, unless the
environment variable "MAKI_DIR" is setdir
properlyval get_default : unit ‑> t