Imported Upstream snapshot 8.3~beta0+13298

1 files changed, 33 insertions, 20 deletions

diff --git a/proofs/evar_refiner.ml b/proofs/evar_refiner.ml
index f4613f8d..e4fab3f2 100644
--- a/proofs/evar_refiner.ml
+++ b/proofs/evar_refiner.ml
@@ -6,45 +6,59 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
-(* $Id: evar_refiner.ml 12102 2009-04-24 10:48:11Z herbelin $ *)
+(* $Id$ *)
 
 open Util
 open Names
 open Term
 open Evd
+open Evarutil
 open Sign
 open Proof_trees
 open Refiner
-open Pretyping
 
 (******************************************)
 (* Instantiation of existential variables *)
 (******************************************)
 
-(* w_tactic pour instantiate *) 
+let depends_on_evar evk _ (pbty,_,t1,t2) =
+  try head_evar t1 = evk
+  with NoHeadEvar ->
+  try head_evar t2 = evk
+  with NoHeadEvar -> false
 
-let w_refine evk (ltac_vars,rawc) evd =
-  if Evd.is_defined (evars_of evd) evk then 
+let define_and_solve_constraints evk c evd =
+  try
+    let evd = define evk c evd in
+    let (evd,pbs) = extract_changed_conv_pbs evd (depends_on_evar evk) in
+    fst (List.fold_left
+      (fun (evd,b as p) (pbty,env,t1,t2) ->
+	if b then Evarconv.evar_conv_x env evd pbty t1 t2 else p) (evd,true)
+      pbs)
+  with e when Pretype_errors.precatchable_exception e ->
+    error "Instance does not satisfy constraints."
+
+let w_refine (evk,evi) (ltac_var,rawc) sigma =
+  if Evd.is_defined sigma evk then
     error "Instantiate called on already-defined evar";
-  let e_info = Evd.find (evars_of evd) evk in
-  let env = Evd.evar_env e_info in
-  let evd',typed_c =
-    try Pretyping.Default.understand_ltac 
-      (evars_of evd) env ltac_vars (OfType (Some e_info.evar_concl)) rawc
+  let env = Evd.evar_env evi in
+  let sigma',typed_c =
+    try Pretyping.Default.understand_ltac true sigma env ltac_var
+	  (Pretyping.OfType (Some evi.evar_concl)) rawc
     with _ ->
       let loc = Rawterm.loc_of_rawconstr rawc in
-      user_err_loc 
+      user_err_loc
         (loc,"",Pp.str ("Instance is not well-typed in the environment of " ^
 			string_of_existential evk))
   in
-    evar_define evk typed_c (evars_reset_evd (evars_of evd') evd)
+  define_and_solve_constraints evk typed_c (evars_reset_evd sigma' sigma)
 
 (* vernac command Existential *)
 
-let instantiate_pf_com n com pfts = 
+let instantiate_pf_com n com pfts =
   let gls = top_goal_of_pftreestate pfts in
-  let sigma = gls.sigma in 
-  let (evk,evi) = 
+  let sigma = gls.sigma in
+  let (evk,evi) =
     let evl = Evarutil.non_instantiated sigma in
       if (n <= 0) then
 	error "incorrect existential variable index"
@@ -52,9 +66,8 @@ let instantiate_pf_com n com pfts =
 	  error "not so many uninstantiated existential variables"
       else
 	List.nth evl (n-1)
-  in 
+  in
   let env = Evd.evar_env evi in
-  let rawc = Constrintern.intern_constr sigma env com in 
-  let evd = create_goal_evar_defs sigma in
-  let evd' = w_refine evk (([],[]),rawc) evd in
-    change_constraints_pftreestate (evars_of evd') pfts
+  let rawc = Constrintern.intern_constr sigma env com in
+  let sigma' = w_refine (evk,evi) (([],[]),rawc) sigma in
+  change_constraints_pftreestate sigma' pfts