(***********************************************************************
    v      *   The Coq Proof Assistant  /  The Coq Development Team     
   <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud 
     \VV/  *************************************************************
      //   *      This file is distributed under the terms of the       
           *       GNU Lesser General Public License Version 2.1        
  ***********************************************************************)

(** Dynamics. Use with extreme care. Not for kids. *)

type t

val create : string -> ('a -> t) * (t -> 'a)
val tag : t -> string