Clean up the legacy refiner implementation.

We avoid using global-access primitives and instead rely on purely functional
passing of the relevant data. Namely, we replace the goal argument with its
environment, and we pass the additional check parameter.

1 files changed, 51 insertions, 61 deletions

diff --git a/proofs/logic.ml b/proofs/logic.ml
index eb0ce23ab7..812fd1d769 100644
--- a/proofs/logic.ml
+++ b/proofs/logic.ml
@@ -71,13 +71,11 @@ let catchable_exception = function
 
 let error_no_such_hypothesis env sigma id = raise (RefinerError (env, sigma, NoSuchHyp id))
 
-(* Tells if the refiner should check that the submitted rules do not
-   produce invalid subgoals *)
-let check = ref false
-let with_check = Flags.with_option check
+(* The check flag tells if the refiner should check that the submitted rules do
+   not produce invalid subgoals *)
 
-let check_typability env sigma c =
-  if !check then fst (type_of env sigma (EConstr.of_constr c)) else sigma
+let check_typability ~check env sigma c =
+  if check then fst (type_of env sigma (EConstr.of_constr c)) else sigma
 
 (************************************************************************)
 (************************************************************************)
@@ -314,8 +312,8 @@ let check_meta_variables env sigma c =
   if not (List.distinct_f Int.compare (collect_meta_variables c)) then
     raise (RefinerError (env, sigma, NonLinearProof c))
 
-let check_conv_leq_goal env sigma arg ty conclty =
-  if !check then
+let check_conv_leq_goal ~check env sigma arg ty conclty =
+  if check then
     let ans = Reductionops.infer_conv env sigma (EConstr.of_constr ty) conclty in
     match ans with
     | Some evm -> evm
@@ -332,28 +330,27 @@ let meta_free_prefix sigma a =
     in a
   with Stop acc -> Array.rev_of_list acc
 
-let goal_type_of env sigma c =
-  if !check then
+let goal_type_of ~check env sigma c =
+  if check then
     let (sigma,t) = type_of env sigma (EConstr.of_constr c) in
     (sigma, EConstr.Unsafe.to_constr t)
   else (sigma, EConstr.Unsafe.to_constr (Retyping.get_type_of env sigma (EConstr.of_constr c)))
 
-let rec mk_refgoals sigma goal goalacc conclty trm =
-  let env = Goal.V82.env sigma goal in
-  let hyps = Goal.V82.hyps sigma goal in
+let rec mk_refgoals ~check env sigma goalacc conclty trm =
+  let hyps = Environ.named_context_val env in
   let mk_goal hyps concl =
     Goal.V82.mk_goal sigma hyps concl
   in
-    if (not !check) && not (occur_meta sigma (EConstr.of_constr trm)) then
+    if (not check) && not (occur_meta sigma (EConstr.of_constr trm)) then
       let t'ty = Retyping.get_type_of env sigma (EConstr.of_constr trm) in
       let t'ty = EConstr.Unsafe.to_constr t'ty in
-      let sigma = check_conv_leq_goal env sigma trm t'ty conclty in
+      let sigma = check_conv_leq_goal ~check env sigma trm t'ty conclty in
         (goalacc,t'ty,sigma,trm)
     else
       match kind trm with
       | Meta _ ->
         let conclty = nf_betaiota env sigma conclty in
-          if !check && occur_meta sigma conclty then
+          if check && occur_meta sigma conclty then
             raise (RefinerError (env, sigma, MetaInType conclty));
           let (gl,ev,sigma) = mk_goal hyps conclty in
           let ev = EConstr.Unsafe.to_constr ev in
@@ -361,9 +358,9 @@ let rec mk_refgoals sigma goal goalacc conclty trm =
           gl::goalacc, conclty, sigma, ev
 
       | Cast (t,k, ty) ->
-        let sigma = check_typability env sigma ty in
-        let sigma = check_conv_leq_goal env sigma trm ty conclty in
-        let res = mk_refgoals sigma goal goalacc (EConstr.of_constr ty) t in
+        let sigma = check_typability ~check env sigma ty in
+        let sigma = check_conv_leq_goal ~check env sigma trm ty conclty in
+        let res = mk_refgoals ~check env sigma goalacc (EConstr.of_constr ty) t in
         (* we keep the casts (in particular VMcast and NATIVEcast) except
            when they are annotating metas *)
         if isMeta t then begin
@@ -386,24 +383,24 @@ let rec mk_refgoals sigma goal goalacc conclty trm =
             let ty = EConstr.Unsafe.to_constr ty in
               goalacc, ty, sigma, f
           else
-            mk_hdgoals sigma goal goalacc f
+            mk_hdgoals ~check env sigma goalacc f
         in
-        let ((acc'',conclty',sigma), args) = mk_arggoals sigma goal acc' hdty l in
-        let sigma = check_conv_leq_goal env sigma trm conclty' conclty in
+        let ((acc'',conclty',sigma), args) = mk_arggoals ~check env sigma acc' hdty l in
+        let sigma = check_conv_leq_goal ~check env sigma trm conclty' conclty in
         let ans = if applicand == f && args == l then trm else mkApp (applicand, args) in
         (acc'',conclty',sigma, ans)
 
       | Proj (p,c) ->
-        let (acc',cty,sigma,c') = mk_hdgoals sigma goal goalacc c in
+        let (acc',cty,sigma,c') = mk_hdgoals ~check env sigma goalacc c in
         let c = mkProj (p, c') in
         let ty = get_type_of env sigma (EConstr.of_constr c) in
         let ty = EConstr.Unsafe.to_constr ty in
           (acc',ty,sigma,c)
 
       | Case (ci,p,c,lf) ->
-        let (acc',lbrty,conclty',sigma,p',c') = mk_casegoals sigma goal goalacc p c in
-        let sigma = check_conv_leq_goal env sigma trm conclty' conclty in
-        let (acc'',sigma,rbranches) = treat_case sigma goal ci lbrty lf acc' in
+        let (acc',lbrty,conclty',sigma,p',c') = mk_casegoals ~check env sigma goalacc p c in
+        let sigma = check_conv_leq_goal ~check env sigma trm conclty' conclty in
+        let (acc'',sigma,rbranches) = treat_case ~check env sigma ci lbrty lf acc' in
         let lf' = Array.rev_of_list rbranches in
         let ans =
           if p' == p && c' == c && Array.equal (==) lf' lf then trm
@@ -414,28 +411,27 @@ let rec mk_refgoals sigma goal goalacc conclty trm =
       | _ ->
         if occur_meta sigma (EConstr.of_constr trm) then
           anomaly (Pp.str "refiner called with a meta in non app/case subterm.");
-        let (sigma, t'ty) = goal_type_of env sigma trm in
-        let sigma = check_conv_leq_goal env sigma trm t'ty conclty in
+        let (sigma, t'ty) = goal_type_of ~check env sigma trm in
+        let sigma = check_conv_leq_goal ~check env sigma trm t'ty conclty in
           (goalacc,t'ty,sigma, trm)
 
 (* Same as mkREFGOALS but without knowing the type of the term. Therefore,
  * Metas should be casted. *)
 
-and mk_hdgoals sigma goal goalacc trm =
-  let env = Goal.V82.env sigma goal in
-  let hyps = Goal.V82.hyps sigma goal in
+and mk_hdgoals ~check env sigma goalacc trm =
+  let hyps = Environ.named_context_val env in
   let mk_goal hyps concl =
     Goal.V82.mk_goal sigma hyps concl in
   match kind trm with
     | Cast (c,_, ty) when isMeta c ->
-        let sigma = check_typability env sigma ty in
+        let sigma = check_typability ~check env sigma ty in
         let (gl,ev,sigma) = mk_goal hyps (nf_betaiota env sigma (EConstr.of_constr ty)) in
         let ev = EConstr.Unsafe.to_constr ev in
         gl::goalacc,ty,sigma,ev
 
     | Cast (t,_, ty) ->
-        let sigma = check_typability env sigma ty in
-        mk_refgoals sigma goal goalacc (EConstr.of_constr ty) t
+        let sigma = check_typability ~check env sigma ty in
+        mk_refgoals ~check env sigma goalacc (EConstr.of_constr ty) t
 
     | App (f,l) ->
         let (acc',hdty,sigma,applicand) =
@@ -443,15 +439,15 @@ and mk_hdgoals sigma goal goalacc trm =
           then
             let l' = meta_free_prefix sigma l in
            (goalacc,EConstr.Unsafe.to_constr (type_of_global_reference_knowing_parameters env sigma (EConstr.of_constr f) l'),sigma,f)
-          else mk_hdgoals sigma goal goalacc f
+          else mk_hdgoals ~check env sigma goalacc f
         in
-        let ((acc'',conclty',sigma), args) = mk_arggoals sigma goal acc' hdty l in
+        let ((acc'',conclty',sigma), args) = mk_arggoals ~check env sigma acc' hdty l in
         let ans = if applicand == f && args == l then trm else mkApp (applicand, args) in
         (acc'',conclty',sigma, ans)
 
     | Case (ci,p,c,lf) ->
-        let (acc',lbrty,conclty',sigma,p',c') = mk_casegoals sigma goal goalacc p c in
-        let (acc'',sigma,rbranches) = treat_case sigma goal ci lbrty lf acc' in
+        let (acc',lbrty,conclty',sigma,p',c') = mk_casegoals ~check env sigma goalacc p c in
+        let (acc'',sigma,rbranches) = treat_case ~check env sigma ci lbrty lf acc' in
         let lf' = Array.rev_of_list rbranches in
         let ans =
           if p' == p && c' == c && Array.equal (==) lf' lf then trm
@@ -460,21 +456,21 @@ and mk_hdgoals sigma goal goalacc trm =
         (acc'',conclty',sigma, ans)
 
     | Proj (p,c) ->
-         let (acc',cty,sigma,c') = mk_hdgoals sigma goal goalacc c in
+         let (acc',cty,sigma,c') = mk_hdgoals ~check env sigma goalacc c in
          let c = mkProj (p, c') in
          let ty = get_type_of env sigma (EConstr.of_constr c) in
          let ty = EConstr.Unsafe.to_constr ty in
            (acc',ty,sigma,c)
 
     | _ ->
-        if !check && occur_meta sigma (EConstr.of_constr trm) then
+        if check && occur_meta sigma (EConstr.of_constr trm) then
           anomaly (Pp.str "refine called with a dependent meta.");
-        let (sigma, ty) = goal_type_of env sigma trm in
+        let (sigma, ty) = goal_type_of env ~check sigma trm in
         goalacc, ty, sigma, trm
 
-and mk_arggoals sigma goal goalacc funty allargs =
+and mk_arggoals ~check env sigma goalacc funty allargs =
   let foldmap (goalacc, funty, sigma) harg =
-    let t = whd_all (Goal.V82.env sigma goal) sigma (EConstr.of_constr funty) in
+    let t = whd_all env sigma (EConstr.of_constr funty) in
     let t = EConstr.Unsafe.to_constr t in
     let rec collapse t = match kind t with
     | LetIn (_, c1, _, b) -> collapse (subst1 c1 b)
@@ -483,19 +479,17 @@ and mk_arggoals sigma goal goalacc funty allargs =
     let t = collapse t in
     match kind t with
     | Prod (_, c1, b) ->
-      let (acc, hargty, sigma, arg) = mk_refgoals sigma goal goalacc (EConstr.of_constr c1) harg in
+      let (acc, hargty, sigma, arg) = mk_refgoals ~check env sigma goalacc (EConstr.of_constr c1) harg in
       (acc, subst1 harg b, sigma), arg
     | _ ->
-      let env = Goal.V82.env sigma goal in
       raise (RefinerError (env,sigma,CannotApply (t, harg)))
   in
   Array.Smart.fold_left_map foldmap (goalacc, funty, sigma) allargs
 
-and mk_casegoals sigma goal goalacc p c =
-  let env = Goal.V82.env sigma goal in
-  let (acc',ct,sigma,c') = mk_hdgoals sigma goal goalacc c in
+and mk_casegoals ~check env sigma goalacc p c =
+  let (acc',ct,sigma,c') = mk_hdgoals ~check env sigma goalacc c in
   let ct = EConstr.of_constr ct in
-  let (acc'',pt,sigma,p') = mk_hdgoals sigma goal acc' p in
+  let (acc'',pt,sigma,p') = mk_hdgoals ~check env sigma acc' p in
   let ((ind, u), spec) =
     try Tacred.find_hnf_rectype env sigma ct
     with Not_found -> anomaly (Pp.str "mk_casegoals.") in
@@ -503,20 +497,19 @@ and mk_casegoals sigma goal goalacc p c =
   let (lbrty,conclty) = type_case_branches_with_names env sigma indspec p c in
   (acc'',lbrty,conclty,sigma,p',c')
 
-and treat_case sigma goal ci lbrty lf acc' =
+and treat_case ~check env sigma ci lbrty lf acc' =
   let rec strip_outer_cast c = match kind c with
   | Cast (c,_,_) -> strip_outer_cast c
   | _ -> c in
   let decompose_app_vect c = match kind c with
   | App (f,cl) -> (f, cl)
   | _ -> (c,[||]) in
-  let env = Goal.V82.env sigma goal in
   Array.fold_left3
     (fun (lacc,sigma,bacc) ty fi l ->
         if isMeta (strip_outer_cast fi) then
           (* Support for non-eta-let-expanded Meta as found in *)
           (* destruct/case with an non eta-let expanded elimination scheme *)
-          let (r,_,s,fi') = mk_refgoals sigma goal lacc ty fi in
+          let (r,_,s,fi') = mk_refgoals ~check env sigma lacc ty fi in
           r,s,(fi'::bacc)
         else
         (* Deal with a branch in expanded form of the form
@@ -537,14 +530,14 @@ and treat_case sigma goal ci lbrty lf acc' =
         if isMeta head then begin
           assert (args = Context.Rel.to_extended_vect mkRel 0 ctx);
           let head' = lift (-n) head in
-          let (r,_,s,head'') = mk_refgoals sigma goal lacc ty head' in
+          let (r,_,s,head'') = mk_refgoals ~check env sigma lacc ty head' in
           let fi' = it_mkLambda_or_LetIn (mkApp (head'',args)) ctx in
           (r,s,fi'::bacc)
         end
         else
           (* Supposed to be meta-free *)
-          let sigma, t'ty = goal_type_of env sigma fi in
-          let sigma = check_conv_leq_goal env sigma fi t'ty ty in
+          let sigma, t'ty = goal_type_of ~check env sigma fi in
+          let sigma = check_conv_leq_goal ~check env sigma fi t'ty ty in
           (lacc,sigma,fi::bacc))
     (acc',sigma,[]) lbrty lf ci.ci_pp_info.cstr_tags
 
@@ -572,20 +565,17 @@ let convert_hyp ~check ~reorder env sigma d =
 (************************************************************************)
 (* Primitive tactics are handled here *)
 
-let prim_refiner r sigma goal =
+let prim_refiner ~check r sigma goal =
   let env = Goal.V82.env sigma goal in
   let cl = Goal.V82.concl sigma goal in
   check_meta_variables env sigma r;
-  let (sgl,cl',sigma,oterm) = mk_refgoals sigma goal [] cl r in
+  let (sgl,cl',sigma,oterm) = mk_refgoals ~check env sigma [] cl r in
   let sgl = List.rev sgl in
   let sigma = Goal.V82.partial_solution env sigma goal (EConstr.of_constr oterm) in
   { Evd.it = sgl; Evd.sigma = sigma; }
 
 let refiner ~check r { Evd.sigma = sigma; Evd.it = goal } =
-  if check then
-    with_check (prim_refiner r sigma) goal
-  else
-    prim_refiner r sigma goal
+  prim_refiner ~check r sigma goal
 
 (* Profiling refiner *)
 let refiner ~check =