functor (Key : Key) ->
sig
type key = Key.t
type t
type sexpable = t
val sexp_of_t : sexpable -> Sexplib.Sexp.t
val t_of_sexp : Sexplib.Sexp.t -> sexpable
val create : (key * float) list -> (t, string) Result.t
val get : t -> key -> float
end