Imported Upstream version 8.0pl1upstream/8.0pl1

1 files changed, 39 insertions, 0 deletions

diff --git a/library/states.ml b/library/states.ml
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+(************************************************************************)
+(*  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        *)
+(************************************************************************)
+
+(* $Id: states.ml,v 1.8.14.1 2004/07/16 19:30:36 herbelin Exp $ *)
+
+open System
+
+type state = Lib.frozen * Summary.frozen
+
+let get_state () =
+  (Lib.freeze(), Summary.freeze_summaries())
+
+let set_state (fl,fs) =
+  Lib.unfreeze fl;
+  Summary.unfreeze_summaries fs
+
+let state_magic_number = 19764
+
+let (extern_state,intern_state) =
+  let (raw_extern, raw_intern) = extern_intern state_magic_number ".coq" in
+  (fun s -> raw_extern s (get_state())),
+  (fun s -> set_state (raw_intern (Library.get_load_path ()) s))
+
+(* Rollback. *)
+
+let freeze = get_state
+let unfreeze = set_state
+
+let with_heavy_rollback f x =
+  let st = get_state () in
+  try 
+    f x
+  with reraise ->
+    (set_state st; raise reraise)