(** This small files declares the exceptions needed by Proofview_gen,
    as Coq's extraction cannot produce exception declarations. *)

(** To help distinguish between exceptions raised by the IO monad from
    the one used natively by Coq, the former are wrapped in
    [Exception].  It is only used internally so that [catch] blocks of
    the IO monad would only catch exceptions raised by the [raise]
    function of the IO monad, and not for instance, by system
    interrupts. Also used in [Proofview] to avoid capturing exception
    from the IO monad ([Proofview] catches errors in its compatibility
    layer, and when lifting goal-level expressions). *)
exception Exception of exn
(** This exception is used to signal abortion in [timeout] functions. *)
exception Timeout
(** This exception is used by the tactics to signal failure by lack of
    successes, rather than some other exceptions (like system
    interrupts). *)
exception TacticFailure of exn