let debug_print = prerr_endline
let type_of_aux' metasenv subst context term =
+ try
+ CicTypeChecker.type_of_aux' ~subst metasenv context term
+ with
+ CicTypeChecker.TypeCheckerFailure msg ->
+ let msg =
+ (sprintf
+ "Kernel Type checking error:
+%s\n%s\ncontext=\n%s\nmetasenv=\n%s\nsubstitution=\n%s\nException:\n%s.\nToo bad."
+ (CicMetaSubst.ppterm subst term)
+ (CicMetaSubst.ppterm [] term)
+ (CicMetaSubst.ppcontext subst context)
+ (CicMetaSubst.ppmetasenv metasenv subst)
+ (CicMetaSubst.ppsubst subst) msg) in
+ raise (AssertFailure msg);;
+(*
try
CicMetaSubst.type_of_aux' metasenv subst context term
with
"Type checking error: %s in context\n%s\nand metasenv\n%s.\nException: %s.\nBroken invariant: unification must be invoked only on well typed terms"
(CicMetaSubst.ppterm subst term)
(CicMetaSubst.ppcontext subst context)
- (CicMetaSubst.ppmetasenv metasenv subst) msg)))
+ (CicMetaSubst.ppmetasenv metasenv subst) msg))) *)
+
+let rec deref subst =
+ function
+ Cic.Meta(n,l) as t ->
+ (try
+ deref subst
+ (CicSubstitution.lift_meta
+ l (snd (CicUtil.lookup_subst n subst)))
+ with
+ CicUtil.Subst_not_found _ -> t)
+ | t -> t
+;;
let rec beta_expand test_equality_only metasenv subst context t arg =
let module S = CicSubstitution in
let rec aux metasenv subst n context t' =
try
let subst,metasenv =
- fo_unif_subst test_equality_only subst context metasenv
- (CicSubstitution.lift n arg) t'
+ fo_unif_subst test_equality_only subst context metasenv
+ (CicSubstitution.lift n arg) t'
in
subst,metasenv,C.Rel (1 + n)
with
aux_exp_named_subst metasenv subst n context exp_named_subst
in
subst,metasenv,C.Var (uri,exp_named_subst')
- | C.Meta (i,l) as t->
- (try
- let (_, t') = CicMetaSubst.lookup_subst i subst in
- aux metasenv subst n context (CicSubstitution.lift_meta l t')
- with CicMetaSubst.SubstNotFound _ ->
- let (subst, metasenv, context, local_context) =
- List.fold_left
- (fun (subst, metasenv, context, local_context) t ->
- match t with
+ | C.Meta (i,l) ->
+ (* andrea: in general, beta_expand can create badly typed
+ terms. This happens quite seldom in practice, UNLESS we
+ iterate on the local context. For this reason, we renounce
+ to iterate and just lift *)
+ let l =
+ List.map
+ (function
+ Some t -> Some (CicSubstitution.lift 1 t)
+ | None -> None) l in
+ subst, metasenv, C.Meta (i,l)
+ (*
+ let (subst, metasenv, context, local_context) =
+ List.fold_right
+ (fun t (subst, metasenv, context, local_context) ->
+ match t with
| None -> (subst, metasenv, context, None :: local_context)
| Some t ->
let (subst, metasenv, t) =
aux metasenv subst n context t
in
- (subst, metasenv, context, Some t :: local_context))
- (subst, metasenv, context, []) l
- in
- (subst, metasenv, C.Meta (i, local_context)))
+ (subst, metasenv, context, Some t :: local_context))
+ l (subst, metasenv, context, [])
+ in
+ prerr_endline ("nuova meta :" ^ (CicPp.ppterm (C.Meta (i, local_context))));
+ (subst, metasenv, C.Meta (i, local_context)) *)
| C.Sort _
| C.Implicit _ as t -> subst,metasenv,t
| C.Cast (te,ty) ->
fl
in
C.Fix (i, substitutedfl)
-*) subst,metasenv,CicMetaSubst.lift subst 1 t'
+*) (* subst,metasenv,CicMetaSubst.lift subst 1 t' *)
+ subst,metasenv,CicSubstitution.lift 1 t'
| C.CoFix (i,fl) ->
(*CSC: not implemented
let tylen = List.length fl in
fl
in
C.CoFix (i, substitutedfl)
-*) subst,metasenv,CicMetaSubst.lift subst 1 t'
+*) (* subst,metasenv,CicMetasubst.lift subst 1 t' *)
+ subst,metasenv,CicSubstitution.lift 1 t'
and aux_exp_named_subst metasenv subst n context ens =
List.fold_right
metasenv context (Cic.Name "Heta") ~typ:argty
in
let subst,metasenv,t' = aux metasenv subst 0 context t in
+ (* prova *)
+ (* old
subst, metasenv, C.Appl [C.Lambda (fresh_name,argty,t') ; arg]
+ *)
+ subst, metasenv, C.Lambda (fresh_name,argty,t')
-and beta_expand_many test_equality_only metasenv subst context t =
- List.fold_left
- (fun (subst,metasenv,t) arg ->
- beta_expand test_equality_only metasenv subst context t arg
- ) (subst,metasenv,t)
+and beta_expand_many test_equality_only metasenv subst context t args =
+ let subst,metasenv,hd =
+ List.fold_right
+ (fun arg (subst,metasenv,t) ->
+ let subst,metasenv,t =
+ beta_expand test_equality_only metasenv subst context t arg in
+ subst,metasenv,t
+ ) args (subst,metasenv,t) in
+ subst,metasenv,hd
(* NUOVA UNIFICAZIONE *)
(* A substitution is a (int * Cic.term) list that associates a
and fo_unif_subst test_equality_only subst context metasenv t1 t2 =
let module C = Cic in
- let module R = CicMetaSubst in
+ let module R = CicReduction in
let module S = CicSubstitution in
+ let t1 = deref subst t1 in
+ let t2 = deref subst t2 in
match (t1, t2) with
(C.Meta (n,ln), C.Meta (m,lm)) when n=m ->
- let ok,subst,metasenv =
- try
- List.fold_left2
- (fun (b,subst,metasenv) t1 t2 ->
- if b then true,subst,metasenv else
- match t1,t2 with
- None,_
- | _,None -> true,subst,metasenv
- | Some t1', Some t2' ->
- (* First possibility: restriction *)
- (* Second possibility: unification *)
- (* Third possibility: convertibility *)
- if R.are_convertible subst context t1' t2' then
- true,subst,metasenv
- else
- (try
- let subst,metasenv =
- fo_unif_subst
- test_equality_only subst context metasenv t1' t2'
- in
- true,subst,metasenv
- with
- Not_found -> false,subst,metasenv)
- ) (true,subst,metasenv) ln lm
- with
- Invalid_argument _ ->
- raise (UnificationFailure (sprintf
- "Error trying to unify %s with %s: the lengths of the two local contexts do not match." (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
- in
- if ok then
- subst,metasenv
- else
- raise (UnificationFailure (sprintf
- "Error trying to unify %s with %s: the algorithm tried to check whether the two substitutions are convertible; if they are not, it tried to unify the two substitutions. No restriction was attempted."
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ let _,subst,metasenv =
+ (try
+ List.fold_left2
+ (fun (j,subst,metasenv) t1 t2 ->
+ match t1,t2 with
+ None,_
+ | _,None -> j+1,subst,metasenv
+ | Some t1', Some t2' ->
+ (* First possibility: restriction *)
+ (* Second possibility: unification *)
+ (* Third possibility: convertibility *)
+ if R.are_convertible ~subst ~metasenv context t1' t2' then
+ j+1,subst,metasenv
+ else
+ (try
+ let subst,metasenv =
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv t1' t2'
+ in
+ j+1,subst,metasenv
+ with
+ Uncertain _
+ | UnificationFailure _ ->
+prerr_endline ("restringo Meta n." ^ (string_of_int n) ^ "on variable n." ^ (string_of_int j));
+ let metasenv, subst =
+ CicMetaSubst.restrict
+ subst [(n,j)] metasenv in
+ j+1,subst,metasenv)
+ ) (1,subst,metasenv) ln lm
+ with
+ Exit ->
+ raise
+ (UnificationFailure "1")
+(*
+ (sprintf
+ "Error trying to unify %s with %s: the algorithm tried to check whether the two substitutions are convertible; if they are not, it tried to unify the two substitutions. No restriction was attempted."
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
+ | Invalid_argument _ ->
+ raise
+ (UnificationFailure "2"))
+(*
+ (sprintf
+ "Error trying to unify %s with %s: the lengths of the two local contexts do not match." (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))))*)
+ in subst,metasenv
| (C.Meta (n,_), C.Meta (m,_)) when n>m ->
fo_unif_subst test_equality_only subst context metasenv t2 t1
| (C.Meta (n,l), t)
fo_unif_subst test_equality_only subst context metasenv
(lower m1 m2) (upper m1 m2)
in
- begin
- try
- let (_, oldt) = CicMetaSubst.lookup_subst n subst in
- let lifted_oldt = S.lift_meta l oldt in
- let ty_lifted_oldt =
- type_of_aux' metasenv subst context lifted_oldt
- in
- let tyt = type_of_aux' metasenv subst context t in
- let (subst, metasenv) =
- fo_unif_subst_ordered test_equality_only subst context metasenv
- tyt ty_lifted_oldt
- in
- fo_unif_subst_ordered
- test_equality_only subst context metasenv t lifted_oldt
- with CicMetaSubst.SubstNotFound _ ->
- (* First of all we unify the type of the meta with the type of the term *)
+ begin
let subst,metasenv =
- let (_,_,meta_type) = CicUtil.lookup_meta n metasenv in
- (try
- let tyt = type_of_aux' metasenv subst context t in
- fo_unif_subst
- test_equality_only
- subst context metasenv tyt (S.lift_meta l meta_type)
- with AssertFailure _ ->
- (* TODO huge hack!!!!
- * we keep on unifying/refining in the hope that the problem will be
- * eventually solved. In the meantime we're breaking a big invariant:
- * the terms that we are unifying are no longer well typed in the
- * current context (in the worst case we could even diverge)
- *)
-(*
-prerr_endline "********* FROM NOW ON EVERY REASONABLE INVARIANT IS BROKEN.";
-prerr_endline "********* PROCEED AT YOUR OWN RISK. AND GOOD LUCK." ;
-*)
- (subst, metasenv))
- in
- let t',metasenv,subst =
- try
- CicMetaSubst.delift n subst context metasenv l t
- with
- (CicMetaSubst.MetaSubstFailure msg)-> raise(UnificationFailure msg)
- | (CicMetaSubst.Uncertain msg) -> raise (Uncertain msg)
- in
- let t'' =
- match t' with
- C.Sort (C.Type u) when not test_equality_only ->
- let u' = CicUniv.fresh () in
- let s = C.Sort (C.Type u') in
- ignore (CicUniv.add_ge (upper u u') (lower u u')) ;
- s
- | _ -> t'
- in
- (* Unifying the types may have already instantiated n. Let's check *)
- try
- let (_, oldt) = CicMetaSubst.lookup_subst n subst in
- let lifted_oldt = S.lift_meta l oldt in
- fo_unif_subst_ordered
- test_equality_only subst context metasenv t lifted_oldt
- with
- CicMetaSubst.SubstNotFound _ ->
- let (_, context, _) = CicUtil.lookup_meta n metasenv in
- let subst = (n, (context, t'')) :: subst in
- let metasenv =
-(* CicMetaSubst.apply_subst_metasenv [n,(context, t'')] metasenv *)
- CicMetaSubst.apply_subst_metasenv subst metasenv
- in
- subst, metasenv
-(* (n,t'')::subst, metasenv *)
- end
+ let (_,_,meta_type) = CicUtil.lookup_meta n metasenv in
+ (try
+ let tyt = type_of_aux' metasenv subst context t in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv tyt (S.lift_meta l meta_type)
+ with
+ UnificationFailure msg
+ | Uncertain msg ->
+ prerr_endline msg;raise (UnificationFailure msg)
+ | AssertFailure _ ->
+ prerr_endline "siamo allo huge hack";
+ (* TODO huge hack!!!!
+ * we keep on unifying/refining in the hope that
+ * the problem will be eventually solved.
+ * In the meantime we're breaking a big invariant:
+ * the terms that we are unifying are no longer well
+ * typed in the current context (in the worst case
+ * we could even diverge) *)
+ (subst, metasenv)) in
+ let t',metasenv,subst =
+ try
+ CicMetaSubst.delift n subst context metasenv l t
+ with
+ (CicMetaSubst.MetaSubstFailure msg)->
+ raise (UnificationFailure msg)
+ | (CicMetaSubst.Uncertain msg) -> raise (Uncertain msg)
+ in
+ let t'' =
+ match t' with
+ C.Sort (C.Type u) when not test_equality_only ->
+ let u' = CicUniv.fresh () in
+ let s = C.Sort (C.Type u') in
+ ignore (CicUniv.add_ge (upper u u') (lower u u')) ;
+ s
+ | _ -> t'
+ in
+ (* Unifying the types may have already instantiated n. Let's check *)
+ try
+ let (_, oldt) = CicUtil.lookup_subst n subst in
+ let lifted_oldt = S.lift_meta l oldt in
+ fo_unif_subst_ordered
+ test_equality_only subst context metasenv t lifted_oldt
+ with
+ CicUtil.Subst_not_found _ ->
+ let (_, context, _) = CicUtil.lookup_meta n metasenv in
+ let subst = (n, (context, t'')) :: subst in
+ let metasenv =
+ List.filter (fun (m,_,_) -> not (n = m)) metasenv in
+ subst, metasenv
+ end
| (C.Var (uri1,exp_named_subst1),C.Var (uri2,exp_named_subst2))
| (C.Const (uri1,exp_named_subst1),C.Const (uri2,exp_named_subst2)) ->
if UriManager.eq uri1 uri2 then
fo_unif_subst_exp_named_subst test_equality_only subst context metasenv
exp_named_subst1 exp_named_subst2
else
- raise (UnificationFailure (sprintf
+ raise (UnificationFailure "3")
+ (* (sprintf
"Can't unify %s with %s due to different constants"
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
| C.MutInd (uri1,i1,exp_named_subst1),C.MutInd (uri2,i2,exp_named_subst2) ->
if UriManager.eq uri1 uri2 && i1 = i2 then
fo_unif_subst_exp_named_subst test_equality_only subst context metasenv
exp_named_subst1 exp_named_subst2
else
- raise (UnificationFailure (sprintf
+ raise (UnificationFailure "4")
+ (* (sprintf
"Can't unify %s with %s due to different inductive principles"
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
| C.MutConstruct (uri1,i1,j1,exp_named_subst1),
C.MutConstruct (uri2,i2,j2,exp_named_subst2) ->
if UriManager.eq uri1 uri2 && i1 = i2 && j1 = j2 then
fo_unif_subst_exp_named_subst test_equality_only subst context metasenv
exp_named_subst1 exp_named_subst2
else
- raise (UnificationFailure (sprintf
+ raise (UnificationFailure "5")
+ (* (sprintf
"Can't unify %s with %s due to different inductive constructors"
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
| (C.Implicit _, _) | (_, C.Implicit _) -> assert false
| (C.Cast (te,ty), t2) -> fo_unif_subst test_equality_only
subst context metasenv te t2
fo_unif_subst
test_equality_only subst context metasenv t2 (S.subst s1 t1)
| (C.Appl l1, C.Appl l2) ->
- let subst,metasenv,t1',t2' =
- match l1,l2 with
- C.Meta (i,_)::_, C.Meta (j,_)::_ when i = j ->
- subst,metasenv,t1,t2
- (* 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
+ (match l1,l2 with
+ C.Meta (i,_)::args1, C.Meta (j,_)::args2 when i = j ->
+ (try
+ List.fold_left2
+ (fun (subst,metasenv) ->
+ fo_unif_subst test_equality_only subst context metasenv)
+ (subst,metasenv) l1 l2
+ with (Invalid_argument msg) -> raise (UnificationFailure msg))
| C.Meta (i,l)::args, _ ->
- let subst,metasenv,t2' =
- beta_expand_many test_equality_only metasenv subst context t2 args
- in
- subst,metasenv,t1,t2'
+ (try
+ let (_,t) = CicUtil.lookup_subst i subst in
+ let lifted = S.lift_meta l t in
+ let reduced = beta_reduce (Cic.Appl (lifted::args)) in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv reduced t2
+ with CicUtil.Subst_not_found _ ->
+ let subst,metasenv,beta_expanded =
+ beta_expand_many
+ test_equality_only metasenv subst context t2 args in
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded)
| _, C.Meta (i,l)::args ->
- let subst,metasenv,t1' =
- beta_expand_many test_equality_only metasenv subst context t1 args
- in
- subst,metasenv,t1',t2
+ (try
+ let (_,t) = CicUtil.lookup_subst i subst in
+ let lifted = S.lift_meta l t in
+ let reduced = beta_reduce (Cic.Appl (lifted::args)) in
+ fo_unif_subst
+ test_equality_only
+ subst context metasenv t1 reduced
+ with CicUtil.Subst_not_found _ ->
+ let subst,metasenv,beta_expanded =
+ beta_expand_many
+ test_equality_only metasenv subst context t1 args in
+ fo_unif_subst test_equality_only subst context metasenv
+ (C.Meta (i,l)) beta_expanded)
| _,_ ->
- subst,metasenv,t1,t2
- in
- begin
- match t1',t2' with
- C.Appl l1, C.Appl l2 ->
- let lr1 = List.rev l1 in
+ let lr1 = List.rev l1 in
let lr2 = List.rev l2 in
let rec fo_unif_l test_equality_only subst metasenv =
function
in
fo_unif_l test_equality_only subst' metasenv' (l1,l2)
in
- fo_unif_l test_equality_only subst metasenv (lr1, lr2)
- | _ -> assert false
- end
+ fo_unif_l test_equality_only subst metasenv (lr1, lr2) )
| (C.MutCase (_,_,outt1,t1',pl1), C.MutCase (_,_,outt2,t2',pl2))->
let subst', metasenv' =
fo_unif_subst test_equality_only subst context metasenv outt1 outt2 in
) (subst'',metasenv'') pl1 pl2
with
Invalid_argument _ ->
- raise (UnificationFailure (sprintf
- "Error trying to unify %s with %s: the number of branches is not the same." (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))))
+ 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
else
- raise (UnificationFailure (sprintf
+ raise (UnificationFailure "6")
+ (* (sprintf
"Can't unify %s with %s because they are not convertible"
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ (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 || R.are_convertible subst context t1 t2 then
+ if t1 = t2 || R.are_convertible ~subst ~metasenv context t1 t2 then
subst, metasenv
else
- raise (UnificationFailure (sprintf
+ raise (UnificationFailure "7")
+ (* (sprintf
"Can't unify %s with %s because they are not convertible"
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
| (_,_) ->
- if R.are_convertible subst context t1 t2 then
+ if R.are_convertible ~subst ~metasenv context t1 t2 then
subst, metasenv
else
- raise (UnificationFailure (sprintf
+ raise (UnificationFailure "8")
+ (* (sprintf
"Can't unify %s with %s because they are not convertible"
- (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2)))
+ (CicMetaSubst.ppterm subst t1) (CicMetaSubst.ppterm subst t2))) *)
and fo_unif_subst_exp_named_subst test_equality_only subst context metasenv
exp_named_subst1 exp_named_subst2
fo_unif_subst false [] context metasenv t1 t2 ;;
let fo_unif_subst subst context metasenv t1 t2 =
- let enrich_msg msg =
- sprintf "Unification error unifying %s of type %s with %s of type %s in context\n%s\nand metasenv\n%s\nbecause %s"
+ let enrich_msg msg = (* "bella roba" *)
+ sprintf "Unification error unifying %s of type %s with %s of type %s in context\n%s\nand metasenv\n%s\nand substitution\n%s\nbecause %s"
(CicMetaSubst.ppterm subst t1)
(try
CicPp.ppterm (type_of_aux' metasenv subst context t1)
CicPp.ppterm (type_of_aux' metasenv subst context t2)
with _ -> "MALFORMED")
(CicMetaSubst.ppcontext subst context)
- (CicMetaSubst.ppmetasenv metasenv subst) msg
+ (CicMetaSubst.ppmetasenv metasenv subst)
+ (CicMetaSubst.ppsubst subst) msg
in
try
fo_unif_subst false subst context metasenv t1 t2
projects / helm.git / blobdiff