- splitted out History module

- exported all_events
- status is now a pair proof * goal _option_ so that completed proofs
  have their entry in the history and could be passed to observers
- added set_metasenv method to change imperatively metasenv
- added explicit notification method notify

diff --git a/helm/ocaml/tactics/statefulProofEngine.ml b/helm/ocaml/tactics/statefulProofEngine.ml
index 94710c412e034972ab65212f0497dd48098e7871..13c1ac5144f66eee541a410072ccef2ccb223063 100644 (file)
--- a/helm/ocaml/tactics/statefulProofEngine.ml
+++ b/helm/ocaml/tactics/statefulProofEngine.ml
@@ -23,84 +23,26 @@
  * http://helm.cs.unibo.it/
  *)
 
-let history_size = 20
+let default_history_size = 20
 
-exception History_failure
 exception No_goal_left
 exception Uri_redefinition
 type event = [ `Proof_changed | `Proof_completed ]
 let all_events = [ `Proof_changed; `Proof_completed ]
 let default_events: event list = [ `Proof_changed ]
 
-type 'a observer =
-  (ProofEngineTypes.status * 'a) option -> (ProofEngineTypes.status * 'a) ->
-    unit
+type proof_status = ProofEngineTypes.proof * ProofEngineTypes.goal option
+
+type 'a observer = (proof_status * 'a) option -> (proof_status * 'a) -> unit
 type observer_id = int
 
 exception Observer_failures of (observer_id * exn) list
 exception Tactic_failure of exn
 exception Data_failure of exn
 
-class ['a] history size =
-  let unsome = function Some x -> x | None -> assert false in
-  object (self)
-
-    val history_data = Array.create (size + 1) None
-
-    val mutable history_hd = 0  (* rightmost index *)
-    val mutable history_cur = 0 (* current index *)
-    val mutable history_tl = 0  (* leftmost index *)
-
-    method private is_empty = history_data.(history_cur) = None
-
-    method push (status: 'a) =
-      if self#is_empty then
-        history_data.(history_cur) <- Some status
-      else begin
-        history_cur <- (history_cur + 1) mod size;
-        history_data.(history_cur) <- Some status;
-        history_hd <- history_cur;  (* throw away fake future line *)
-        if history_hd = history_tl then (* tail overwritten *)
-          history_tl <- (history_tl + 1) mod size
-      end
-
-    method undo = function
-      | 0 -> unsome history_data.(history_cur)
-      | steps when steps > 0 ->
-          let max_undo_steps =
-            if history_cur >= history_tl then
-              history_cur - history_tl
-            else
-              history_cur + (size - history_tl)
-          in
-          if steps > max_undo_steps then
-            raise History_failure;
-          history_cur <- history_cur - steps;
-          if history_cur < 0 then (* fix underflow *)
-            history_cur <- size + history_cur;
-          unsome history_data.(history_cur)
-      | steps (* when steps > 0 *) -> self#redo ~-steps
-
-    method redo = function
-      | 0 -> unsome history_data.(history_cur)
-      | steps when steps > 0 ->
-          let max_redo_steps =
-            if history_hd >= history_cur then
-              history_hd - history_cur
-            else
-              history_hd + (size - history_cur)
-          in
-          if steps > max_redo_steps then
-            raise History_failure;
-          history_cur <- (history_cur + steps) mod size;
-          unsome history_data.(history_cur)
-      | steps (* when steps > 0 *) -> self#undo ~-steps
-
-  end
-
 class ['a] status
-  ?uri ~typ ?(body = Cic.Meta (1, [])) ?(metasenv = [1,[],typ])
-  init_data compute_data ()
+  ?(history_size = default_history_size)
+  ?uri ~typ ~body ~metasenv init_data compute_data ()
   =
   let next_observer_id =
     let next_id = ref 0 in
@@ -129,18 +71,21 @@ class ['a] status
 
       (* assumption: all items in history are uncompleted proofs, thus option on
       * goal could be ignored and goal are stored as bare integers *)
-    val history = new history history_size
+    val history = new History.history history_size
 
     initializer
       history#push self#internal_status
 
     method proof = _proof
-    method goal =
-      match _goal with Some goal -> goal | None -> raise No_goal_left
-    method private status = (_proof, self#active_goal)  (* logic status *)
-    method private set_status (proof, goal) =
+    method private status = (_proof, _goal)  (* logic status *)
+    method private set_status (proof, (goal: int option)) =
       _proof <- proof;
-      _goal <- Some goal
+      _goal <- goal
+
+    method goal =
+      match _goal with
+      | Some goal -> goal
+      | None -> raise No_goal_left
 
       (* what will be kept in history *)
     method private internal_status = (self#status, _data)
@@ -154,7 +99,7 @@ class ['a] status
       try
         self#update_data old_internal_status;
         history#push self#internal_status;
-        self#notify (Some old_internal_status)
+        self#private_notify (Some old_internal_status)
       with (Data_failure _) as exn ->
         self#set_internal_status old_internal_status;
         raise exn
@@ -164,6 +109,10 @@ class ['a] status
     method body     = let (_, _, body, _)     = _proof in body
     method typ      = let (_, _, _, typ)      = _proof in typ
 
+    method set_metasenv metasenv =
+      let (uri, _, body, typ) = _proof in
+      _proof <- (uri, metasenv, body, typ)
+
     method set_uri uri =
       let (old_uri, metasenv, body, typ) = _proof in
       if old_uri <> None then
@@ -174,16 +123,11 @@ class ['a] status
       let (_, metasenv, _, _) = _proof in
       CicUtil.lookup_meta goal metasenv
 
-    method private active_goal =
-      match _goal with
-      | None -> raise No_goal_left
-      | Some goal -> goal
-
     method apply_tactic tactic =
       let old_internal_status = self#internal_status in
       let (new_proof, new_goals) =
         try
-          ProofEngineTypes.apply_tactic tactic (_proof, self#active_goal)
+          ProofEngineTypes.apply_tactic tactic (_proof, self#goal)
         with exn -> raise (Tactic_failure exn)
       in
       _proof <- new_proof;
@@ -191,12 +135,12 @@ class ['a] status
       try
         self#update_data old_internal_status;
         history#push self#internal_status;
-        self#notify (Some old_internal_status)
+        self#private_notify (Some old_internal_status)
       with (Data_failure _) as exn ->
         self#set_internal_status old_internal_status;
         raise exn
 
-    method proof_completed = _goal <> None
+    method proof_completed = _goal = None
 
     method attach_observer ?(interested_in = default_events) observer
       =
@@ -222,7 +166,7 @@ class ['a] status
           Hashtbl.replace observers event new_observers)
         all_events
 
-    method private notify old_internal_status =
+    method private private_notify old_internal_status =
       let cur_internal_status = (self#status, _data) in
       let exns = ref [] in
       let notify (id, observer) =
@@ -250,14 +194,16 @@ class ['a] status
     method undo ?(steps = 1) () =
       let ((proof, goal), data) = history#undo steps in
       _proof <- proof;
-      _goal <- Some goal;
+      _goal <- goal;
       _data <- data;
-      self#notify None
+      self#private_notify None
 
     method redo ?(steps = 1) () = self#undo ~steps:~-steps ()
 
+    method notify = self#private_notify None
+
   end
 
-let trivial_status ?uri ~typ ?body ?metasenv () =
-  new status ?uri ~typ ?body ?metasenv (fun _ -> ()) (fun _ _ -> ()) ()
+let trivial_status ?uri ~typ ~body ~metasenv () =
+  new status ?uri ~typ ~body ~metasenv (fun _ -> ()) (fun _ _ -> ()) ()
 

diff --git a/helm/ocaml/tactics/statefulProofEngine.mli b/helm/ocaml/tactics/statefulProofEngine.mli
index 9a4cf78254aad02a17342b2c1974d787eed0bccb..4198876ca239b4e191395fbac58efc788b0801d9 100644 (file)
--- a/helm/ocaml/tactics/statefulProofEngine.mli
+++ b/helm/ocaml/tactics/statefulProofEngine.mli
@@ -28,19 +28,22 @@
 exception No_goal_left
 exception Uri_redefinition
 
-  (** can't undo/redo one or more actions *)
-exception History_failure
-
 type event = [ `Proof_changed | `Proof_completed ]
 
+val all_events: event list
+
+  (** from our point of view a status is the status of an incomplete proof, thus
+  * we have an optional goal which is None if the proof is not yet completed
+  * (i.e. some goal is still open) *)
+type proof_status = ProofEngineTypes.proof * ProofEngineTypes.goal option
+
   (** Proof observer. First callback argument is Some extended_status
   * when a 'real 'change of the proof happened and None when Proof_changed event
-  * was triggered by a time travel by the means of undo/redo actions. Embedded
-  * status is the status _before_ the current change. Second status is the
-  * status reached _after_ the current change. *)
-type 'a observer =
-  (ProofEngineTypes.status * 'a) option -> (ProofEngineTypes.status * 'a) ->
-    unit
+  * was triggered by a time travel by the means of undo/redo actions or by an
+  * external "#notify" invocation. Embedded status is the status _before_ the
+  * current change. Second status is the status reached _after_ the current
+  * change. *)
+type 'a observer = (proof_status * 'a) option -> (proof_status * 'a) -> unit
 
   (** needed to detach previously attached observers *)
 type observer_id
@@ -57,10 +60,11 @@ exception Data_failure of exn
 (** {2 OO interface} *)
 
 class ['a] status:
+  ?history_size:int ->  (** default 20 *)
   ?uri:UriManager.uri ->
-  typ:Cic.term -> ?body:Cic.term -> ?metasenv:Cic.metasenv ->
-  (ProofEngineTypes.proof * ProofEngineTypes.goal option -> 'a) ->
-  (ProofEngineTypes.status * 'a -> ProofEngineTypes.status -> 'a) ->
+  typ:Cic.term -> body:Cic.term -> metasenv:Cic.metasenv ->
+  (proof_status -> 'a) -> (* init data *)
+  (proof_status * 'a -> proof_status -> 'a) ->  (* update data *)
   unit ->
   object
 
@@ -69,13 +73,16 @@ class ['a] status:
     method body: Cic.term
     method typ: Cic.term
 
+    (** change metasenv _without_ triggering any notification *)
+    method set_metasenv: Cic.metasenv -> unit
+
     (** goal -> conjecture
     * @raise CicUtil.Meta_not_found *)
     method conjecture: int -> Cic.conjecture
 
     method proof_completed: bool
     method goal: int              (** @raise No_goal_left *)
-    method set_goal: int -> unit  (** @raise No_goal_left *)
+    method set_goal: int -> unit  (** @raise Data_failure *)
 
     method uri: UriManager.uri option
     method set_uri: UriManager.uri -> unit  (** @raise Uri_redefinition *)
@@ -100,11 +107,14 @@ class ['a] status:
 
     method detach_observer: observer_id -> unit
 
+    (** force a notification to all observer, old status is passed as None *)
+    method notify: unit
+
   end
 
 val trivial_status:
   ?uri:UriManager.uri ->
-  typ:Cic.term -> ?body:Cic.term -> ?metasenv:Cic.metasenv ->
+  typ:Cic.term -> body:Cic.term -> metasenv:Cic.metasenv ->
   unit ->
     unit status