Here comes the commit, announced long ago, of the new tactic engine.

This is a fairly large commit (around 140 files and 7000 lines of code
impacted), it will cause some troubles for sure (I've listed the know
regressions below, there is bound to be more).
At this state of developpement it brings few features to the user, as
the old tactics were
ported with no change. Changes are on the side of the developer mostly.

Here comes a list of the major changes. I will stay brief, but the code
is hopefully well documented so that it is reasonably easy to infer the
details from it.

Feature developer-side:
* Primitives for a "real" refine tactic (generating a goal for each
evar).
* Abstract type of tactics, goals and proofs
* Tactics can act on several goals (formally all the focused goals). An
interesting consequence of this is that the tactical (. ; [ . | ... ])
can be separated in two
tacticals (. ; .) and ( [ . | ... ] ) (although there is a conflict for
this particular syntax). We can also imagine a tactic to reorder the
goals.
* Possibility for a tactic to pass a value to following tactics (a
typical example is
an intro function which tells the following tactics which name it
introduced).
* backtracking primitives for tactics (it is now possible to implement a
tactical '+'
  with (a+b);c equivalent to (a;c+b;c) (itself equivalent to
(a;c||b;c)). This is a valuable
  tool to implement tactics like "auto" without nowing of the
implementation of tactics.
* A notion of proof modes, which allows to dynamically change the parser
for tactics. It is controlled at user level with the keywords Set
Default Proof Mode (this is the proof mode which is loaded at the start
of each proof) and Proof Mode (switches the proof mode of the current
proof) to control them.
* A new primitive Evd.fold_undefined which operates like an Evd.fold,
except it only goes through the evars whose body is Evar_empty. This is
a common operation throughout the code,
some of the fold-and-test-if-empty occurences have been replaced by
fold_undefined. For now,
it is only implemented as a fold-and-test, but we expect to have some
optimisations coming some day, as there can be a lot of evars in an
evar_map with this new implementation (I've observed a couple of
thousands), whereas there are rarely more than a dozen undefined ones.
Folding being a linear operation, this might result in a significant
speed-up.
* The declarative mode has been moved into the plugins. This is made
possible by the proof mode feature. I tried to document it so that it
can serve as a tutorial for a tactic mode plugin.

Features user-side:
* Unfocus does not go back to the root of the proof if several Focus-s
have been performed.
  It only goes back to the point where it was last focused.
* experimental (non-documented) support of keywords
BeginSubproof/EndSubproof:
  BeginSubproof focuses on first goal, one can unfocus only with
EndSubproof, and only
  if the proof is completed for that goal.
* experimental (non-documented) support for bullets ('+', '-' and '*')
  they act as hierarchical BeginSubproof/EndSubproof:
  First time one uses '+' (for instance) it focuses on first goal, when
the subproof is
  completed, one can use '+' again which unfocuses and focuses on next
first goal.
  Meanwhile, one cas use '*' (for instance) to focus more deeply.

Known regressions:
* The xml plugin had some functions related to proof trees. As the
structure of proof changed significantly, they do not work anymore.
* I do not know how to implement info or show script in this new engine.
Actually I don't even know what they were suppose to actually mean in
earlier versions either. I wager they would require some calm thinking
before going back to work.
* Declarative mode not entirely working (in particular proofs by
induction need to be restored).
* A bug in the inversion tactic (observed in some contributions)
* A bug in Program (observed in some contributions)
* Minor change in the 'old' type of tactics causing some contributions
to fail.
* Compilation time takes about 10-15% longer for unknown reasons (I
suspect it might be linked to the fact that I don't perform any
reduction at QED-s, and also to some linear operations on evar_map-s
(see Evd.fold_undefined above)).


git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@12961 85f007b7-540e-0410-9357-904b9bb8a0f7

2 files changed, 23 insertions, 42 deletions

diff --git a/ide/coq.ml b/ide/coq.ml
index 87f0c35e6..9b0afc7be 100644
--- a/ide/coq.ml
+++ b/ide/coq.ml
@@ -19,7 +19,6 @@ open Printer
 open Environ
 open Evarutil
 open Evd
-open Decl_mode
 open Hipattern
 open Tacmach
 open Reductionops
@@ -90,11 +89,6 @@ let version () =
 let is_in_loadpath coqtop dir =
   Library.is_in_load_paths (System.physical_path_of_string dir)
 
-let is_in_proof_mode () =
-  match Decl_mode.get_current_mode () with
-      Decl_mode.Mode_none -> false
-    | _ -> true
-
 let user_error_loc l s =
   raise (Stdpp.Exc_located (l, Util.UserError ("CoqIde", s)))
 
@@ -169,11 +163,6 @@ let rec attribute_of_vernac_command = function
   | VernacSolve _ -> [SolveCommand]
   | VernacSolveExistential _ -> [SolveCommand]
 
-  (* MMode *)
-  | VernacDeclProof -> [SolveCommand]
-  | VernacReturn -> [SolveCommand]
-  | VernacProofInstr _ -> [SolveCommand]
-
   (* Auxiliary file and library management *)
   | VernacRequireFrom _ -> []
   | VernacAddLoadPath _ -> []
@@ -241,9 +230,15 @@ let rec attribute_of_vernac_command = function
   | VernacProof (Tacexpr.TacId []) -> [OtherStatePreservingCommand]
   | VernacProof _ -> []
 
+  | VernacProofMode _ -> []
+
+  | VernacSubproof _ -> [SolveCommand]
+  | VernacEndSubproof _ -> [SolveCommand]
+
   (* Toplevel control *)
   | VernacToplevelControl _ -> []
 
+
   (* Extensions *)
   | VernacExtend ("Subtac_Obligations", _) -> [GoalStartingCommand]
   | VernacExtend _ -> []
@@ -508,13 +503,13 @@ let hyp_next_tac sigma env (id,_,ast) =
     ("inversion clear "^id_s), ("inversion_clear "^id_s^".\n")
   ]
 
-let concl_next_tac concl =
+let concl_next_tac sigma concl =
   let expand s = (s,s^".\n") in
   List.map expand ([
     "intro";
     "intros";
     "intuition"
-  ] @ (if Hipattern.is_equality_type concl.Evd.evar_concl then [
+  ] @ (if Hipattern.is_equality_type (Goal.V82.concl sigma concl) then [
     "reflexivity";
     "discriminate";
     "symmetry"
@@ -538,30 +533,26 @@ let concl_next_tac concl =
 let goals coqtop =
   PrintOpt.enforce_hack ();
   let pfts = Pfedit.get_pftreestate () in
-  let sigma = Tacmach.evc_of_pftreestate pfts in
-  let (all_goals,_) = Refiner.frontier (Refiner.proof_of_pftreestate pfts) in
+  let { it=all_goals ; sigma=sigma } = Proof.V82.subgoals pfts in
   if all_goals = [] then
     begin
       Message (
-        match Decl_mode.get_end_command pfts with
-          | Some c -> "Subproof completed, now type "^c^".\n"
-          | None ->
-              let exl = Evarutil.non_instantiated sigma in
-              if exl = [] then "Proof Completed.\n" else
-                ("No more subgoals but non-instantiated existential variables:\n"^
-                 string_of_ppcmds (pr_evars_int 1 exl)))
+        let exl = Evarutil.non_instantiated sigma in
+        if exl = [] then "Proof Completed.\n" else
+          ("No more subgoals but non-instantiated existential variables:\n"^
+             string_of_ppcmds (pr_evars_int 1 exl)))
     end
   else
     begin
       let process_goal g =
-        let env = Evd.evar_env g in
+        let env = Goal.V82.env sigma g in
         let ccl =
-          string_of_ppcmds (pr_ltype_env_at_top env g.Evd.evar_concl) in
+          string_of_ppcmds (pr_ltype_env_at_top env (Goal.V82.concl sigma g)) in
         let process_hyp h_env d acc =
           (string_of_ppcmds (pr_var_decl h_env d), hyp_next_tac sigma h_env d)::acc in
         let hyps =
           List.rev (Environ.fold_named_context process_hyp env ~init:[]) in
-        (hyps,(ccl,concl_next_tac g))
+        (hyps,(ccl,concl_next_tac sigma g))
       in
       Goals (List.map process_goal all_goals)
     end
diff --git a/ide/coqide.ml b/ide/coqide.ml
index 4fa0c28f5..5d604a62b 100644
--- a/ide/coqide.ml
+++ b/ide/coqide.ml
@@ -730,14 +730,10 @@ object(self)
                 (String.make previous_line_spaces ' ')
       end
 
+
   method show_goals =
     try
-      match Decl_mode.get_current_mode () with
-          Decl_mode.Mode_none -> ()
-        | Decl_mode.Mode_tactic ->
-            Ideproof.display (Ideproof.mode_tactic (fun _ _ -> ())) proof_view (Coq.goals Coq.dummy_coqtop)
-        | Decl_mode.Mode_proof ->
-            Ideproof.display Ideproof.mode_cesar proof_view (Coq.goals Coq.dummy_coqtop)
+      Ideproof.display (Ideproof.mode_tactic (fun _ _ -> ())) proof_view (Coq.goals Coq.dummy_coqtop)
     with e ->
       prerr_endline ("Don't worry be happy despite: "^Printexc.to_string e)
 
@@ -747,15 +743,10 @@ object(self)
     if not full_goal_done then
       begin
         try
-          match Decl_mode.get_current_mode () with
-              Decl_mode.Mode_none -> ()
-            | Decl_mode.Mode_tactic ->
-                Ideproof.display
-                  (Ideproof.mode_tactic (fun s () -> ignore (self#insert_this_phrase_on_success
-                                                            true true false ("progress "^s) s)))
-                  proof_view (Coq.goals Coq.dummy_coqtop)
-            | Decl_mode.Mode_proof ->
-                Ideproof.display Ideproof.mode_cesar proof_view (Coq.goals Coq.dummy_coqtop)
+          Ideproof.display
+            (Ideproof.mode_tactic (fun s () -> ignore (self#insert_this_phrase_on_success
+                                                         true true false ("progress "^s) s)))
+            proof_view (Coq.goals Coq.dummy_coqtop)
         with e -> prerr_endline (Printexc.to_string e)
       end
 
@@ -787,9 +778,8 @@ object(self)
       try
         full_goal_done <- false;
         prerr_endline "Send_to_coq starting now";
-        Decl_mode.clear_daimon_flag ();
         let r = Coq.interp Coq.dummy_coqtop verbosely phrase in
-        let is_complete = not (Decl_mode.get_daimon_flag ()) in
+        let is_complete = true in
         let msg = read_stdout () in
         sync display_output msg;
         Some (is_complete,r)