You can search for identifiers within the package.
in-package search v0.2.0
type level
val older : level -> level -> bool
val size : unit -> int
val depth : unit -> int
val level : unit -> level
val levels : unit -> level list
val nb_choice_points : unit -> int
exception Level_not_found of level
val cut : level -> unit
exception Fail of string
val fail : string -> 'a
val trail : (unit -> unit) -> unit
type 'a ref
val ref : 'a -> 'a ref
val set : 'a ref -> 'a -> unit
val get : 'a ref -> 'a