From: Claudio Sacerdoti Coen <claudio.sacerdoticoen@unibo.it>
Date: Wed, 7 Apr 2004 14:30:41 +0000 (+0000)
Subject: Added flag test_equality_only to are_convertible to better implement
X-Git-Tag: dead_dir_walking~73
X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=515c95d5d339bc457772d3dd08765b55ad140054;p=helm.git

Added flag test_equality_only to are_convertible to better implement
the <=_{\beta\delta\iota\zeta} relation.
---

diff --git a/helm/ocaml/cic_proof_checking/cicReductionNaif.ml b/helm/ocaml/cic_proof_checking/cicReductionNaif.ml
index 436200644..ea7fb4229 100644
--- a/helm/ocaml/cic_proof_checking/cicReductionNaif.ml
+++ b/helm/ocaml/cic_proof_checking/cicReductionNaif.ml
@@ -184,8 +184,8 @@ t in prerr_endline "DOPO WHD" ; flush stderr ; res
 (* t1, t2 must be well-typed *)
 let are_convertible =
  let module U = UriManager in
- let rec aux context t1 t2 =
-  let aux2 t1 t2 =
+ let rec aux test_equality_only context t1 t2 =
+  let aux2 test_equality_only t1 t2 =
    (* this trivial euristic cuts down the total time of about five times ;-) *)
    (* this because most of the time t1 and t2 are "sintactically" the same   *)
    if t1 = t2 then
@@ -200,7 +200,7 @@ let are_convertible =
              (try
                List.fold_right2
                 (fun (uri1,x) (uri2,y) b ->
-                  U.eq uri1 uri2 && aux context x y && b
+                  U.eq uri1 uri2 && aux test_equality_only context x y && b
                 ) exp_named_subst1 exp_named_subst2 true 
               with
                Invalid_argument _ -> false
@@ -213,21 +213,23 @@ let are_convertible =
                  match t1,t2 with
                     None,_
                   | _,None  -> true
-                  | Some t1',Some t2' -> aux context t1' t2'
+                  | Some t1',Some t2' -> aux test_equality_only context t1' t2'
               ) true l1 l2
-        | (C.Sort s1, C.Sort s2) -> true (*CSC da finire con gli universi *)
+        | (C.Sort s1, C.Sort s2) when s1 = s2 || s2 = C.Type -> true
         | (C.Prod (name1,s1,t1), C.Prod(_,s2,t2)) ->
-           aux context s1 s2 &&
-            aux ((Some (name1, (C.Decl s1)))::context) t1 t2
+           aux true context s1 s2 &&
+            aux test_equality_only ((Some (name1, (C.Decl s1)))::context) t1 t2
         | (C.Lambda (name1,s1,t1), C.Lambda(_,s2,t2)) ->
-           aux context s1 s2 &&
-            aux ((Some (name1, (C.Decl s1)))::context) t1 t2
+           aux test_equality_only context s1 s2 &&
+            aux test_equality_only ((Some (name1, (C.Decl s1)))::context) t1 t2
         | (C.LetIn (name1,s1,t1), C.LetIn(_,s2,t2)) ->
-           aux context s1 s2 &&
-            aux ((Some (name1, (C.Def (s1,None))))::context) t1 t2
+           aux test_equality_only context s1 s2 &&
+            aux test_equality_only
+             ((Some (name1, (C.Def (s1,None))))::context) t1 t2
         | (C.Appl l1, C.Appl l2) ->
            (try
-             List.fold_right2 (fun  x y b -> aux context x y && b) l1 l2 true 
+             List.fold_right2
+              (fun  x y b -> aux test_equality_only context x y && b) l1 l2 true
             with
              Invalid_argument _ -> false
            )
@@ -236,7 +238,7 @@ let are_convertible =
              (try
                List.fold_right2
                 (fun (uri1,x) (uri2,y) b ->
-                  U.eq uri1 uri2 && aux context x y && b
+                  U.eq uri1 uri2 && aux test_equality_only context x y && b
                 ) exp_named_subst1 exp_named_subst2 true 
               with
                Invalid_argument _ -> false
@@ -248,7 +250,7 @@ let are_convertible =
              (try
                List.fold_right2
                 (fun (uri1,x) (uri2,y) b ->
-                  U.eq uri1 uri2 && aux context x y && b
+                  U.eq uri1 uri2 && aux test_equality_only context x y && b
                 ) exp_named_subst1 exp_named_subst2 true 
               with
                Invalid_argument _ -> false
@@ -260,16 +262,19 @@ let are_convertible =
              (try
                List.fold_right2
                 (fun (uri1,x) (uri2,y) b ->
-                  U.eq uri1 uri2 && aux context x y && b
+                  U.eq uri1 uri2 && aux test_equality_only context x y && b
                 ) exp_named_subst1 exp_named_subst2 true 
               with
                Invalid_argument _ -> false
              )
         | (C.MutCase (uri1,i1,outtype1,term1,pl1),
            C.MutCase (uri2,i2,outtype2,term2,pl2)) -> 
-            U.eq uri1 uri2 && i1 = i2 && aux context outtype1 outtype2 &&
-             aux context term1 term2 &&
-             List.fold_right2 (fun x y b -> b && aux context x y) pl1 pl2 true
+            U.eq uri1 uri2 && i1 = i2 &&
+             aux test_equality_only context outtype1 outtype2 &&
+             aux test_equality_only context term1 term2 &&
+             List.fold_right2
+              (fun x y b -> b && aux test_equality_only context x y)
+              pl1 pl2 true
         | (C.Fix (i1,fl1), C.Fix (i2,fl2)) ->
            let tys =
             List.map (function (n,_,ty,_) -> Some (C.Name n,(C.Decl ty))) fl1
@@ -277,8 +282,9 @@ let are_convertible =
             i1 = i2 &&
              List.fold_right2
               (fun (_,recindex1,ty1,bo1) (_,recindex2,ty2,bo2) b ->
-                b && recindex1 = recindex2 && aux context ty1 ty2 &&
-                 aux (tys@context) bo1 bo2)
+                b && recindex1 = recindex2 &&
+                 aux test_equality_only context ty1 ty2 &&
+                 aux test_equality_only (tys@context) bo1 bo2)
               fl1 fl2 true
         | (C.CoFix (i1,fl1), C.CoFix (i2,fl2)) ->
            let tys =
@@ -287,23 +293,24 @@ let are_convertible =
             i1 = i2 &&
              List.fold_right2
               (fun (_,ty1,bo1) (_,ty2,bo2) b ->
-                b && aux context ty1 ty2 && aux (tys@context) bo1 bo2)
+                b && aux test_equality_only context ty1 ty2 &&
+                 aux test_equality_only (tys@context) bo1 bo2)
               fl1 fl2 true
         | (C.Cast _, _) | (_, C.Cast _)
         | (C.Implicit _, _) | (_, C.Implicit _) ->
-           raise (Impossible 3) (* we don't trust our whd ;-) *)
+            assert false
         | (_,_) -> false
     end
   in
-   if aux2 t1 t2 then true
+   if aux2 test_equality_only t1 t2 then true
    else
     begin
      debug t1 [t2] "PREWHD";
-     let t1' = whd context t1 
-     and t2' = whd context t2 in
+     let t1' = whd context t1 in
+     let t2' = whd context t2 in
       debug t1' [t2'] "POSTWHD";
-      aux2 t1' t2'
+      aux2 test_equality_only t1' t2'
     end
  in
-  aux
+  aux false
 ;;