Module Facile.Stak

module Stak: sig .. end

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