generalize no more required before elim

[helm.git] / helm / software / components / ng_kernel / nCicReduction.ml

diff --git a/helm/software/components/ng_kernel/nCicReduction.ml b/helm/software/components/ng_kernel/nCicReduction.ml
index 73f78dc3693deab8606a4d5f894a3f27443dba54..c15e75a872a89c14c31e3035918fd16dfbcd2211 100644 (file)
--- a/helm/software/components/ng_kernel/nCicReduction.ml
+++ b/helm/software/components/ng_kernel/nCicReduction.ml
@@ -171,7 +171,7 @@ let whd = R.whd
 let (===) x y = Pervasives.compare x y = 0 ;;
 
 (* t1, t2 must be well-typed *)
-let are_convertible whd ?(subst=[])  =
+let are_convertible ?(subst=[]) get_relevance =
  let rec aux test_eq_only context t1 t2 =
    let rec alpha_eq test_eq_only t1 t2 =
      if t1 === t2 then
@@ -182,21 +182,22 @@ let are_convertible whd ?(subst=[])  =
            NCicEnvironment.universe_leq a b
        | (C.Sort (C.Type a), C.Sort (C.Type b)) -> 
            NCicEnvironment.universe_eq a b
-       | (C.Sort s1,C.Sort (C.Type _)) -> (not test_eq_only)
-       | (C.Sort s1, C.Sort s2) -> s1 = s2
+       | (C.Sort C.Prop,C.Sort (C.Type _)) -> (not test_eq_only)
+       | (C.Sort C.Prop, C.Sort C.Prop) -> true
 
        | (C.Prod (name1,s1,t1), C.Prod(_,s2,t2)) ->
            aux true context s1 s2 &&
            aux test_eq_only ((name1, C.Decl s1)::context) t1 t2
-       | (C.Lambda (name1,s1,t1), C.Lambda(_,s2,t2)) ->
-          aux true context s1 s2 && 
+       | (C.Lambda (name1,s1,t1), C.Lambda(_,_,t2)) ->
+          (* thanks to inversion of well typedness, the source 
+           * of these lambdas must be already convertible *)
           aux test_eq_only ((name1, C.Decl s1)::context) t1 t2
        | (C.LetIn (name1,ty1,s1,t1), C.LetIn(_,ty2,s2,t2)) ->
           aux test_eq_only context ty1 ty2 &&
           aux test_eq_only context s1 s2 &&
           aux test_eq_only ((name1, C.Def (s1,ty1))::context) t1 t2
 
-       | (C.Meta (n1,(s1, C.Irl i1)), C.Meta (n2,(s2, C.Irl i2))) 
+       | (C.Meta (n1,(s1, C.Irl _)), C.Meta (n2,(s2, C.Irl _))) 
           when n1 = n2 && s1 = s2 -> true
        | (C.Meta (n1,(s1, l1)), C.Meta (n2,(s2, l2))) when n1 = n2 &&
           let l1 = NCicUtils.expand_local_context l1 in
@@ -221,19 +222,15 @@ let are_convertible whd ?(subst=[])  =
               aux test_eq_only context t1 term
            with NCicUtils.Subst_not_found _ -> false)
 
-       | (C.Appl (C.Const r1::tl1), C.Appl (C.Const r2::tl2)) ->
-          r1 = r2 &&
-           let relevance = NCicEnvironment.get_relevance r1 in
+       | (C.Appl (hd1::tl1), C.Appl (hd2::tl2)) ->
+           aux test_eq_only context hd1 hd2 &&
+          let relevance = get_relevance ~subst context hd1 in
            (try
              HExtlib.list_forall_default3
               (fun t1 t2 b -> not b || aux test_eq_only context t1 t2)
               tl1 tl2 true relevance
             with Invalid_argument _ -> false)
 
-       | (C.Appl l1, C.Appl l2) ->
-          (try List.for_all2 (aux test_eq_only context) l1 l2
-           with Invalid_argument _ -> false)
-
        | (C.Match (ref1,outtype1,term1,pl1),
           C.Match (ref2,outtype2,term2,pl2)) -> 
            Ref.eq ref1 ref2 &&
@@ -288,8 +285,6 @@ let are_convertible whd ?(subst=[])  =
   aux false 
 ;;
 
-let are_convertible = are_convertible whd
-
 let rec head_beta_reduce ?(delta=max_int) ?(upto=(-1)) t l =
  match upto, t, l with
   | 0, C.Appl l1, _ -> C.Appl (l1 @ l)