exception UnificationFailure of string Lazy.t;;
exception Uncertain of string Lazy.t;;
exception AssertFailure of string Lazy.t;;
+exception KeepReducing of string Lazy.t;;
let (===) x y = Pervasives.compare x y = 0 ;;
-let uncert_exc metasenv subst context t1 t2 =
- Uncertain (lazy (
+let mk_msg metasenv subst context t1 t2 =
+ (lazy (
"Can't unify " ^ NCicPp.ppterm ~metasenv ~subst ~context t1 ^
" with " ^ NCicPp.ppterm ~metasenv ~subst ~context t2))
-;;
-
-let fail_exc metasenv subst context t1 t2 =
- UnificationFailure (lazy (
- "Can't unify " ^ NCicPp.ppterm ~metasenv ~subst ~context t1 ^
- " with " ^ NCicPp.ppterm ~metasenv ~subst ~context t2));
-;;
let mk_appl ~upto hd tl =
NCicReduction.head_beta_reduce ~upto
module C = NCic;;
module Ref = NReference;;
-let debug = false;;
+let debug = ref false;;
let indent = ref "";;
-let pp =
- if debug then
- fun s -> prerr_endline (Printf.sprintf "%-20s" !indent ^ " " ^ Lazy.force s)
+let pp s =
+ if !debug then
+ prerr_endline (Printf.sprintf "%-20s" !indent ^ " " ^ Lazy.force s)
else
- fun _ -> ()
+ ()
;;
let inside c =
indent := !indent ^ String.make 1 c;
- if debug then prerr_endline ("{{{" ^ !indent ^ " ")
+ if !debug then prerr_endline ("{{{" ^ !indent ^ " ")
;;
let outside ok =
- if debug then prerr_endline "}}}";
+ if !debug then prerr_endline "}}}";
if not ok then pp (lazy "exception raised!");
try
indent := String.sub !indent 0 (String.length !indent -1)
with NCicUtils.Subst_not_found _ -> false
;;
-let rec mk_irl =
- function
- 0 -> []
- | n -> NCic.Rel n :: mk_irl (n-1)
+let rec mk_irl stop base =
+ if base > stop then []
+ else (NCic.Rel base) :: mk_irl stop (base+1)
;;
(* the argument must be a term in whd *)
metasenv, subst, bo
| (arg,ty)::tail ->
pp(lazy("arg{ " ^
- NCicPp.ppterm ~metasenv ~subst ~context:context_of_args arg ^ ":" ^
+ NCicPp.ppterm ~metasenv ~subst ~context:context_of_args arg ^ " : " ^
NCicPp.ppterm ~metasenv ~subst ~context:context_of_args ty));
let metasenv, subst, telescopic_ty =
if processed_args = [] then metasenv, subst, ty else
let _ = pp(lazy("delift")) in
- delift_type_wrt_terms rdb metasenv subst context_of_args ty
- (List.rev processed_args)
+ delift_type_wrt_terms rdb metasenv subst context
+ (NCicSubstitution.lift n ty)
+ (List.map (NCicSubstitution.lift n) (List.rev processed_args))
in
- pp(lazy("arg}"));
+ pp(lazy("arg} "^NCicPp.ppterm ~metasenv ~subst ~context telescopic_ty));
let name = "HBeta"^string_of_int n in
let metasenv, subst, bo =
mk_lambda metasenv subst ((name,NCic.Decl telescopic_ty)::context) (n+1)
assert(has_tag ((=)`IsSort) tags);
metasenv, subst, t
| _ ->
- let exc_to_be = fail_exc metasenv subst context (NCic.Meta (n,lc)) t in
+ let exc_to_be =
+ UnificationFailure (mk_msg metasenv subst context (NCic.Meta (n,lc)) t)
+ in
let t, ty_t =
try t, NCicTypeChecker.typeof ~subst ~metasenv context t
with
let subst = subst_entry :: subst in
let metasenv = List.filter (fun x,_ -> i <> x) metasenv in
metasenv, subst, m, j
+ | NCic.Appl (NCic.Meta _ as hd :: args) as t ->
+ let metasenv, subst, lambda_Mj =
+ lambda_intros rdb metasenv subst context t args
+ in
+ let metasenv,subst= unify true metasenv subst context hd lambda_Mj in
+ let t = NCicReduction.whd ~subst context t in
+ let _result = sortify metasenv subst t in
+ (* untested, maybe dead, code *) assert false;
| t ->
if could_reduce t then raise (Uncertain(lazy "not a sort"))
else raise (UnificationFailure(lazy "not a sort"))
in
let tags, ctx, ty = NCicUtils.lookup_meta n metasenv in
(* instantiation *)
-
- (* sortification:
- - Meta sort === t -> check t is sort or sortify
- - add tag `IsSort and set cc=[] to n and its pile
- - se gli ancestor non sono sorte o meta... bum...
- - cambiare in-place menv
- - geneare meta fresh sorta e dall'alto al basso
- - Meta _ === Meta sort -> sortify n (i.e. add `IsSort)
- *)
pp (lazy(string_of_int n ^ " := 111 = "^
NCicPp.ppterm ~metasenv ~subst ~context t));
let (metasenv, subst), t =
(* conjecture: always fail --> occur check *)
unify test_eq_only metasenv subst context oldt t
with NCicUtils.Subst_not_found _ ->
+ let metasenv, tags =
+ let rec aux = function
+ | NCic.Meta (j,lc) ->
+ (try
+ let _, _, t, _ = NCicUtils.lookup_subst j subst in
+ aux (NCicSubstitution.subst_meta lc t)
+ with NCicUtils.Subst_not_found _ ->
+ let tags', ctx, ty = NCicUtils.lookup_meta j metasenv in
+ let metasenv = List.remove_assoc j metasenv in
+ let tags = tags @ tags' in
+ (j, (tags, ctx, ty)) :: metasenv, tags)
+ | _ -> metasenv, tags
+ in
+ aux t
+ in
(* by cumulativity when unify(?,Type_i)
* we could ? := Type_j with j <= i... *)
let subst = (n, (tags, ctx, t, ty)) :: subst in
and unify rdb test_eq_only metasenv subst context t1 t2 =
(*D*) inside 'U'; try let rc =
- let fo_unif test_eq_only metasenv subst t1 t2 =
+ let fo_unif test_eq_only metasenv subst (norm1,t1) (norm2,t2) =
(*D*) inside 'F'; try let rc =
pp (lazy(" " ^ NCicPp.ppterm ~metasenv ~subst ~context t1 ^ " ==?== " ^
NCicPp.ppterm ~metasenv ~subst ~context t2 ^ ppmetasenv
~subst metasenv));
+ pp (lazy(" " ^ NCicPp.ppterm ~metasenv ~subst:[] ~context t1 ^ " ==??== " ^
+ NCicPp.ppterm ~metasenv ~subst:[] ~context t2 ^ ppmetasenv
+ ~subst metasenv));
if t1 === t2 then
metasenv, subst
else
assert false
| (C.Sort (C.Type a), C.Sort (C.Type b)) when not test_eq_only ->
if NCicEnvironment.universe_leq a b then metasenv, subst
- else raise (fail_exc metasenv subst context t1 t2)
+ else raise (UnificationFailure (mk_msg metasenv subst context t1 t2))
| (C.Sort (C.Type a), C.Sort (C.Type b)) ->
if NCicEnvironment.universe_eq a b then metasenv, subst
- else raise (fail_exc metasenv subst context t1 t2)
+ else raise (UnificationFailure (mk_msg metasenv subst context t1 t2))
| (C.Sort C.Prop,C.Sort (C.Type _)) ->
if (not test_eq_only) then metasenv, subst
- else raise (fail_exc metasenv subst context t1 t2)
+ else raise (UnificationFailure (mk_msg metasenv subst context t1 t2))
| (C.Lambda (name1,s1,t1), C.Lambda(_,s2,t2))
| (C.Prod (name1,s1,t1), C.Prod(_,s2,t2)) ->
let term2 = NCicSubstitution.subst_meta lc2 term in
unify rdb test_eq_only metasenv subst context term1 term2
with NCicUtils.Subst_not_found _-> raise (UnificationFailure msg))
+
+ | NCic.Appl (NCic.Meta (i,_)::_ as l1),
+ NCic.Appl (NCic.Meta (j,_)::_ as l2) when i=j ->
+ (try
+ List.fold_left2
+ (fun (metasenv, subst) t1 t2 ->
+ unify rdb test_eq_only metasenv subst context t1 t2)
+ (metasenv,subst) l1 l2
+ with Invalid_argument _ ->
+ raise (UnificationFailure (mk_msg metasenv subst context t1 t2)))
| _, NCic.Meta (n, _) when is_locked n subst ->
(let (metasenv, subst), i =
metasenv, ((i, (name, ctx, term, ty)) :: subst)
with Not_found -> assert false))
- | C.Meta (n,lc), t ->
- (try
- let _,_,term,_ = NCicUtils.lookup_subst n subst in
- let term = NCicSubstitution.subst_meta lc term in
- unify rdb test_eq_only metasenv subst context term t
- with NCicUtils.Subst_not_found _->
- instantiate rdb test_eq_only metasenv subst context n lc
- (NCicReduction.head_beta_reduce ~subst t) false)
+ | C.Meta (n,lc), t when List.mem_assoc n subst ->
+ let _,_,term,_ = NCicUtils.lookup_subst n subst in
+ let term = NCicSubstitution.subst_meta lc term in
+ unify rdb test_eq_only metasenv subst context term t
- | t, C.Meta (n,lc) ->
- (try
- let _,_,term,_ = NCicUtils.lookup_subst n subst in
- let term = NCicSubstitution.subst_meta lc term in
- unify rdb test_eq_only metasenv subst context t term
- with NCicUtils.Subst_not_found _->
- instantiate rdb test_eq_only metasenv subst context n lc
- (NCicReduction.head_beta_reduce ~subst t) true)
+ | t, C.Meta (n,lc) when List.mem_assoc n subst ->
+ let _,_,term,_ = NCicUtils.lookup_subst n subst in
+ let term = NCicSubstitution.subst_meta lc term in
+ unify rdb test_eq_only metasenv subst context t term
| NCic.Appl (NCic.Meta (i,l)::args), _ when List.mem_assoc i subst ->
let _,_,term,_ = NCicUtils.lookup_subst i subst in
unify rdb test_eq_only metasenv subst context t1
(mk_appl ~upto:(List.length args) term args)
- | NCic.Appl (NCic.Meta (i,_)::_ as l1),
- NCic.Appl (NCic.Meta (j,_)::_ as l2) when i=j ->
- (try
- List.fold_left2
- (fun (metasenv, subst) t1 t2 ->
- unify rdb test_eq_only metasenv subst context t1 t2)
- (metasenv,subst) l1 l2
- with Invalid_argument _ ->
- raise (fail_exc metasenv subst context t1 t2))
+ | C.Meta (n,lc), t ->
+ instantiate rdb test_eq_only metasenv subst context n lc
+ (NCicReduction.head_beta_reduce ~subst t) false
+
+ | t, C.Meta (n,lc) ->
+ instantiate rdb test_eq_only metasenv subst context n lc
+ (NCicReduction.head_beta_reduce ~subst t) true
| NCic.Appl (NCic.Meta (i,l)::args), _ ->
let metasenv, subst, lambda_Mj =
lambda_intros rdb metasenv subst context t1 args
in
let metasenv, subst =
+ try
unify rdb test_eq_only metasenv subst context
(C.Meta (i,l)) lambda_Mj
+ with UnificationFailure msg | Uncertain msg ->
+ (* failure: let's try again argument vs argument *)
+ raise (KeepReducing msg)
in
let metasenv, subst =
unify rdb test_eq_only metasenv subst context t1 t2
lambda_intros rdb metasenv subst context t2 args
in
let metasenv, subst =
+ try
unify rdb test_eq_only metasenv subst context
lambda_Mj (C.Meta (i,l))
+ with UnificationFailure msg | Uncertain msg ->
+ (* failure: let's try again argument vs argument *)
+ raise (KeepReducing msg)
in
let metasenv, subst =
unify rdb test_eq_only metasenv subst context t1 t2
in
metasenv, subst, relevance)
(metasenv, subst, relevance) tl1 tl2
- with Invalid_argument _ ->
- raise (uncert_exc metasenv subst context t1 t2)
+ with
+ Invalid_argument _ ->
+ raise (Uncertain (mk_msg metasenv subst context t1 t2))
+ | UnificationFailure _ | Uncertain _ when not (norm1 && norm2) ->
+ raise (KeepReducing (mk_msg metasenv subst context t1 t2))
in
metasenv, subst
| _ -> false
in
if not (Ref.eq ref1 ref2) then
- raise (uncert_exc metasenv subst context t1 t2)
+ raise (Uncertain (mk_msg metasenv subst context t1 t2))
else
let metasenv, subst =
unify rdb test_eq_only metasenv subst context outtype1 outtype2 in
(metasenv, subst) pl1 pl2
with Invalid_argument _ -> assert false)
| (C.Implicit _, _) | (_, C.Implicit _) -> assert false
- | _ when NCicUntrusted.metas_of_term subst context t1 = [] &&
- NCicUntrusted.metas_of_term subst context t2 = [] ->
- raise (fail_exc metasenv subst context t1 t2)
- | _ -> raise (uncert_exc metasenv subst context t1 t2)
+ | _ when norm1 && norm2 ->
+ if (could_reduce t1 || could_reduce t2) then
+ raise (Uncertain (mk_msg metasenv subst context t1 t2))
+ else
+ raise (UnificationFailure (mk_msg metasenv subst context t1 t2))
+ | _ -> raise (KeepReducing (mk_msg metasenv subst context t1 t2))
(*D*) in outside true; rc with exn -> outside false; raise exn
in
- let try_hints metasenv subst t1 t2 (* exc*) =
+ let try_hints metasenv subst (_,t1 as mt1) (_,t2 as mt2) (* exc*) =
(*D*) inside 'H'; try let rc =
-(*
- prerr_endline ("\nProblema:\n" ^
+ pp(lazy ("\nProblema:\n" ^
NCicPp.ppterm ~metasenv ~subst ~context t1 ^ " =?= " ^
- NCicPp.ppterm ~metasenv ~subst ~context t2);
-*)
+ NCicPp.ppterm ~metasenv ~subst ~context t2));
let candidates =
NCicUnifHint.look_for_hint rdb metasenv subst context t1 t2
in
try
(*D*) inside 'K'; try let rc =
let metasenv,subst =
- fo_unif test_eq_only metasenv subst t1 c1 in
+ fo_unif test_eq_only metasenv subst mt1 (false,c1) in
let metasenv,subst =
- fo_unif test_eq_only metasenv subst c2 t2 in
+ fo_unif test_eq_only metasenv subst (false,c2) mt2 in
let metasenv,subst =
List.fold_left
(fun (metasenv, subst) (x,y) ->
unify rdb test_eq_only metasenv subst context x y)
(metasenv, subst) premises
in
+ pp(lazy("FUNZIONA!"));
Some (metasenv, subst)
(*D*) in outside true; rc with exn -> outside false; raise exn
with
- UnificationFailure _ | Uncertain _ ->
- cand_iter tl
+ KeepReducing _ | UnificationFailure _ | Uncertain _ -> cand_iter tl
in
cand_iter candidates
(*D*) in outside true; rc with exn -> outside false; raise exn
=
assert (not (norm1 && norm2));
if norm1 then
- x1,NCicReduction.reduce_machine ~delta:(height_of t2 -1) ~subst context m2
+ x1,NCicReduction.reduce_machine ~delta:0 ~subst context m2
else if norm2 then
- NCicReduction.reduce_machine ~delta:(height_of t1 -1) ~subst context m1,x2
+ NCicReduction.reduce_machine ~delta:0 ~subst context m1,x2
else
let h1 = height_of t1 in
let h2 = height_of t2 in
in
let hh1,hh2,todo=check_stack (List.rev s1) (List.rev s2) relevance [] in
try
- let metasenv,subst = fo_unif test_eq_only metasenv subst hh1 hh2 in
+ let metasenv,subst =
+ fo_unif test_eq_only metasenv subst (norm1,hh1) (norm2,hh2) in
List.fold_left
(fun (metasenv,subst) (x1,x2,r) ->
unif_from_stack x1 x2 r metasenv subst
) (metasenv,subst) todo
- with UnificationFailure _ | Uncertain _ when not (norm1 && norm2) ->
+ with
+ | KeepReducing _ ->
+ assert (not (norm1 && norm2));
unif_machines metasenv subst (small_delta_step ~subst m1 m2)
+ | UnificationFailure _ | Uncertain _ when (not (norm1 && norm2))
+ -> unif_machines metasenv subst (small_delta_step ~subst m1 m2)
+ | UnificationFailure msg
+ when could_reduce (NCicReduction.unwind (fst m1))
+ || could_reduce (NCicReduction.unwind (fst m2))
+ -> raise (Uncertain msg)
(*D*) in outside true; rc with exn -> outside false; raise exn
in
- try fo_unif test_eq_only metasenv subst t1 t2
+ try fo_unif test_eq_only metasenv subst (false,t1) (false,t2)
with
- | UnificationFailure msg as exn ->
- (try
- unif_machines metasenv subst
- (put_in_whd (0,[],t1,[]) (0,[],t2,[]))
- with
- | UnificationFailure _ -> raise (UnificationFailure msg)
- | Uncertain _ -> raise exn)
- | Uncertain msg as exn ->
- match try_hints metasenv subst t1 t2 with
- | Some x -> x
- | None ->
- try
- unif_machines metasenv subst
- (put_in_whd (0,[],t1,[]) (0,[],t2,[]))
- with
- | UnificationFailure _ -> raise (UnificationFailure msg)
- | Uncertain _ -> raise exn
- (*D*) in outside true; rc with exn -> outside false; raise exn
+ | UnificationFailure _ as exn -> raise exn
+ | KeepReducing _ | Uncertain _ as exn ->
+ let (t1,norm1 as tm1),(t2,norm2 as tm2) =
+ put_in_whd (0,[],t1,[]) (0,[],t2,[])
+ in
+ (match
+ try_hints metasenv subst
+ (norm1,NCicReduction.unwind t1) (norm2,NCicReduction.unwind t2)
+ with
+ | Some x -> x
+ | None ->
+ match exn with
+ | KeepReducing msg ->
+ (try
+ unif_machines metasenv subst (tm1,tm2)
+ with
+ | UnificationFailure _ -> raise (UnificationFailure msg)
+ | Uncertain _ -> raise (Uncertain msg)
+ | KeepReducing _ -> assert false)
+ | Uncertain _ -> raise exn
+ | _ -> assert false)
+ (*D*) in outside true; rc with KeepReducing _ -> assert false | exn -> outside false; raise exn
and delift_type_wrt_terms rdb metasenv subst context t args =
+ let lc = List.rev args @ mk_irl (List.length context) (List.length args+1) in
let (metasenv, subst), t =
try
NCicMetaSubst.delift
with UnificationFailure _ | Uncertain _ -> None
in
indent := ind; res)
- metasenv subst context 0 (0,NCic.Ctx (args @
- List.rev (mk_irl (List.length context)))) t
- with NCicMetaSubst.MetaSubstFailure _ -> (metasenv, subst), t
+ metasenv subst context 0 (0,NCic.Ctx lc) t
+ with
+ NCicMetaSubst.MetaSubstFailure _
+ | NCicMetaSubst.Uncertain _ -> (metasenv, subst), t
in
metasenv, subst, t
;;