+ fo_unif_subst test_equality_only
+ subst' ((Some (n1,(C.Decl s1)))::context) metasenv' t1 t2 ugraph1
+ | (C.LetIn (_,s1,t1), t2)
+ | (t2, C.LetIn (_,s1,t1)) ->
+ fo_unif_subst
+ test_equality_only subst context metasenv t2 (S.subst s1 t1) ugraph
+ | (C.Appl l1, C.Appl l2) ->
+(* WAS BEFORE ----------
+ let subst,metasenv,t1',t2',ugraph1 =
+ match l1,l2 with
+ C.Meta (i,_)::_, C.Meta (j,_)::_ when i = j ->
+ subst,metasenv,t1,t2,ugraph
+ (* In the first two cases when we reach the next begin ... end
+ section useless work is done since, by construction, the list
+ of arguments will be equal.
+ *)
+----------------- *)
+ (* andrea: this case should be probably rewritten in the
+ spirit of deref *)
+ let rec beta_reduce =
+ function
+ (Cic.Appl (Cic.Lambda (_,_,t)::he'::tl')) ->
+ let he'' = CicSubstitution.subst he' t in
+ if tl' = [] then
+ he''
+ else
+ beta_reduce (Cic.Appl(he''::tl'))
+ | t -> t in
+ let exists_a_meta l =
+ List.exists (function Cic.Meta _ -> true | _ -> false) l
+ in
+ (match l1,l2 with
+ C.Meta (i,_)::args1, C.Meta (j,_)::args2 when i = j ->
+ (try
+ List.fold_left2
+ (fun (subst,metasenv,ugraph) t1 t2 ->
+ fo_unif_subst
+ test_equality_only subst context metasenv t1 t2 ugraph)
+ (subst,metasenv,ugraph) l1 l2
+ with (Invalid_argument msg) -> raise (UnificationFailure msg))
+ | C.Meta (i,l)::args, _ when not(exists_a_meta args) ->
+ (* we verify that none of the args is a Meta, since beta expanding
+ with respoect to a metavariable makes no sense
+ *)
+ (try
+ let (_,t,_) = CicUtil.lookup_subst i subst in
+ let lifted = S.subst_meta l t in
+ let reduced = beta_reduce (Cic.Appl (lifted::args)) in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv reduced t2 ugraph
+ with CicUtil.Subst_not_found _ ->
+ let subst,metasenv,beta_expanded,ugraph1 =
+ beta_expand_many
+ test_equality_only metasenv subst context t2 args ugraph
+ in
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded ugraph1)
+ | _, C.Meta (i,l)::args when not(exists_a_meta args) ->
+ (try
+ let (_,t,_) = CicUtil.lookup_subst i subst in
+ let lifted = S.subst_meta l t in
+ let reduced = beta_reduce (Cic.Appl (lifted::args)) in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv t1 reduced ugraph
+ with CicUtil.Subst_not_found _ ->
+ let subst,metasenv,beta_expanded,ugraph1 =
+ beta_expand_many
+ test_equality_only metasenv subst context t1 args ugraph in
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded ugraph1)
+ | _,_ ->
+ let lr1 = List.rev l1 in
+ let lr2 = List.rev l2 in
+ let rec
+ fo_unif_l test_equality_only subst metasenv (l1,l2) ugraph =
+ match (l1,l2) with
+ [],_
+ | _,[] -> assert false
+ | ([h1],[h2]) ->
+ fo_unif_subst
+ test_equality_only subst context metasenv h1 h2 ugraph
+ | ([h],l)
+ | (l,[h]) ->
+ fo_unif_subst test_equality_only subst context metasenv
+ h (C.Appl (List.rev l)) ugraph
+ | ((h1::l1),(h2::l2)) ->
+ let subst', metasenv',ugraph1 =
+ fo_unif_subst
+ test_equality_only subst context metasenv h1 h2 ugraph
+ in
+ fo_unif_l
+ test_equality_only subst' metasenv' (l1,l2) ugraph1
+ in
+ fo_unif_l
+ test_equality_only subst metasenv (lr1, lr2) ugraph)(**)
+ | (C.MutCase (_,_,outt1,t1',pl1), C.MutCase (_,_,outt2,t2',pl2))->
+ let subst', metasenv',ugraph1 =
+ fo_unif_subst test_equality_only subst context metasenv outt1 outt2
+ ugraph in
+ let subst'',metasenv'',ugraph2 =
+ fo_unif_subst test_equality_only subst' context metasenv' t1' t2'
+ ugraph1 in
+ (try
+ List.fold_left2
+ (fun (subst,metasenv,ugraph) t1 t2 ->
+ fo_unif_subst
+ test_equality_only subst context metasenv t1 t2 ugraph
+ ) (subst'',metasenv'',ugraph2) pl1 pl2
+ with
+ Invalid_argument _ ->
+ raise (UnificationFailure "6"))
+ (* (sprintf
+ "Error trying to unify %s with %s: the number of branches is not the same." (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))) *)
+ | (C.Rel _, _) | (_, C.Rel _) ->
+ if t1 = t2 then
+ subst, metasenv,ugraph
+ else
+ raise (UnificationFailure "6")
+ (* (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
+ | (C.Sort _ ,_) | (_, C.Sort _)
+ | (C.Const _, _) | (_, C.Const _)
+ | (C.MutInd _, _) | (_, C.MutInd _)
+ | (C.MutConstruct _, _) | (_, C.MutConstruct _)
+ | (C.Fix _, _) | (_, C.Fix _)
+ | (C.CoFix _, _) | (_, C.CoFix _) ->
+ if t1 = t2 then
+ subst, metasenv, ugraph
+ else
+ let b,ugraph1 =
+ R.are_convertible ~subst ~metasenv context t1 t2 ugraph
+ in
+ if b then
+ subst, metasenv, ugraph1
+ else
+ raise (UnificationFailure "7")
+ (* (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))) *)
+ | (C.Prod _, t2) ->
+ let t2' = R.whd ~subst context t2 in
+ (match t2' with
+ C.Prod _ ->
+ fo_unif_subst test_equality_only
+ subst context metasenv t1 t2' ugraph
+ | _ -> raise (UnificationFailure "8"))
+ | (t1, C.Prod _) ->
+ let t1' = R.whd ~subst context t1 in
+ (match t1' with
+ C.Prod _ ->
+ fo_unif_subst test_equality_only
+ subst context metasenv t1' t2 ugraph
+ | _ -> raise (UnificationFailure "9"))
+ | (_,_) ->
+ let b,ugraph1 =
+ R.are_convertible ~subst ~metasenv context t1 t2 ugraph
+ in
+ if b then
+ subst, metasenv, ugraph1
+ else
+ raise (UnificationFailure "10")
+ (* (sprintf
+ "Can't unify %s with %s because they are not convertible"
+ (CicMetaSubst.ppterm subst t1)
+ (CicMetaSubst.ppterm subst t2))) *)