From: Wilmer Ricciotti Date: Thu, 19 Nov 2009 10:26:27 +0000 (+0000) Subject: - Added a swap parameter to the unification procedure X-Git-Tag: make_still_working~3202 X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;ds=sidebyside;h=a4615d355dba036f1faf4aa3306e005da5e839a0;p=helm.git - Added a swap parameter to the unification procedure - Fixed a bug in the metavariable restriction algorithm, which resulted in bad metavariable local contexts. --- diff --git a/helm/software/components/ng_refiner/nCicMetaSubst.ml b/helm/software/components/ng_refiner/nCicMetaSubst.ml index ce0021d3d..549f06f85 100644 --- a/helm/software/components/ng_refiner/nCicMetaSubst.ml +++ b/helm/software/components/ng_refiner/nCicMetaSubst.ml @@ -133,27 +133,33 @@ let rec force_does_not_occur metasenv subst restrictions t = NCicUtils.Subst_not_found _ -> (* we ignore the subst since restrict will take care of already * instantiated/restricted metavariabels *) - let (metasenv,subst as ms), restrictions_for_n, l' = - let l = NCicUtils.expand_local_context lc in - - let ms, _, restrictions_for_n, l = + let l = NCicUtils.expand_local_context lc in + let sl = List.map (NCicSubstitution.lift shift) l in + let (metasenv,subst as ms), _, restrictions_for_n, l' = List.fold_right (fun t (ms, i, restrictions_for_n, l) -> try - let ms, t = aux (k-shift) ms t in + (*pp (lazy ("L'ORLO DELLA FOSSA: k= " ^ string_of_int k ^ " shift=" ^ + string_of_int shift ^ " t=" ^ NCicPp.ppterm ~metasenv ~subst ~context:[] t));*) + let ms, t = aux k ms t in + (*pp (lazy ("LA FOSSA: " ^ NCicPp.ppterm ~metasenv ~subst ~context:[] t));*) ms, i-1, restrictions_for_n, t::l with Occur -> ms, i-1, i::restrictions_for_n, l) - l (ms, List.length l, [], []) - in - - ms, restrictions_for_n, pack_lc (shift, NCic.Ctx l) + sl (ms, List.length l, [], []) in if restrictions_for_n = [] then - ms, if l = l' then orig else NCic.Meta (n, l') + ms, if sl = l' then orig else ( + (*pp (lazy ("FINITO: " ^ NCicPp.ppterm ~metasenv:[] ~subst:[] + ~context:[] (NCic.Meta (n,pack_lc (0, NCic.Ctx l')))));*) + NCic.Meta (n, pack_lc (0, NCic.Ctx l')) + ) else + let l' = pack_lc (0, NCic.Ctx l') in + let _ = pp (lazy ("restrictions for n are:" ^ String.concat "," (List.map string_of_int restrictions_for_n))) in let metasenv, subst, newmeta, more_restricted = restrict metasenv subst n restrictions_for_n in + let _ = pp (lazy ("more restricted: " ^String.concat "," (List.map string_of_int more_restricted))) in let l' = purge_restricted restrictions more_restricted l' in (metasenv, subst), NCic.Meta (newmeta, l')) | t -> NCicUntrusted.map_term_fold_a (fun _ k -> k+1) k aux ms t @@ -162,6 +168,8 @@ let rec force_does_not_occur metasenv subst restrictions t = and force_does_not_occur_in_context metasenv subst restrictions = function | name, NCic.Decl t as orig -> + (* pp (lazy ("CCC: hd is" ^ NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] t ^ + "\nCCC: restrictions are:" ^ String.concat "," (List.map string_of_int restrictions)));*) let (metasenv, subst), t' = force_does_not_occur metasenv subst restrictions t in metasenv, subst, (if t == t' then orig else (name,NCic.Decl t')) @@ -234,6 +242,9 @@ and restrict metasenv subst i (restrictions as orig) = let reloc_irl = mk_perforated_irl 0 (List.length ctx) restrictions in let subst_entry = i, (name, ctx, NCic.Meta (j, reloc_irl), ty) in + (* pp (lazy ("BBB: dopo1 \n" ^ NCicPp.ppsubst ~metasenv [subst_entry])); + pp (lazy ("BBB: dopo2 \n" ^ NCicPp.ppsubst ~metasenv (subst_entry::subst))); + pp (lazy ("BBB: dopo metasenv\n" ^ NCicPp.ppmetasenv ~subst [metasenv_entry]));*) let diff = List.filter (fun x -> not (List.mem x orig)) restrictions in List.map (fun (n,_) as orig -> if i = n then metasenv_entry else orig) diff --git a/helm/software/components/ng_refiner/nCicUnification.ml b/helm/software/components/ng_refiner/nCicUnification.ml index 0f73dbc5c..805ea859f 100644 --- a/helm/software/components/ng_refiner/nCicUnification.ml +++ b/helm/software/components/ng_refiner/nCicUnification.ml @@ -288,7 +288,7 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap = ~unify:(fun m s c t1 t2 -> let ind = !indent in let res = - try Some (unify rdb test_eq_only m s c t1 t2 ) + try Some (unify rdb test_eq_only m s c t1 t2 false) with UnificationFailure _ | Uncertain _ -> None in indent := ind; res) @@ -308,7 +308,7 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap = let oldt = NCicSubstitution.subst_meta lc oldt in let t = NCicSubstitution.subst_meta lc t in (* conjecture: always fail --> occur check *) - unify rdb test_eq_only metasenv subst context t oldt + unify rdb test_eq_only metasenv subst context t oldt false with NCicUtils.Subst_not_found _ -> move_to_subst n (attrs,cc,t,ty) metasenv subst in @@ -348,7 +348,7 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap = ppterm ~metasenv ~subst ~context ty ^ "=<=" ^ ppterm ~metasenv ~subst ~context ty_t)); let metasenv, subst = - unify rdb false metasenv subst context ty_t ty in + unify rdb false metasenv subst context ty_t ty false in delift_to_subst test_eq_only n lc (attrs,cc,ty) t context metasenv subst | _ -> assert false) @@ -361,7 +361,7 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap = NCicMetaSubst.delift ~unify:(fun m s c t1 t2 -> let ind = !indent in - let res = try Some (unify rdb test_eq_only m s c t1 t2 ) + let res = try Some (unify rdb test_eq_only m s c t1 t2 false ) with UnificationFailure _ | Uncertain _ -> None in indent := ind; res) @@ -381,20 +381,24 @@ let rec instantiate rdb test_eq_only metasenv subst context n lc t swap = ppterm ~metasenv ~subst ~context lty ^ "=<=" ^ ppterm ~metasenv ~subst ~context ty_t)); let metasenv, subst = - unify rdb false metasenv subst context ty_t lty + unify rdb false metasenv subst context ty_t lty false in delift_to_subst test_eq_only n lc (attrs,cc,ty) t context metasenv subst) (*D*) in outside None; rc with exn -> outside (Some exn); raise exn -and unify rdb test_eq_only metasenv subst context t1 t2 = +and unify rdb test_eq_only metasenv subst context t1 t2 swap = (*D*) inside 'U'; try let rc = let fo_unif test_eq_only metasenv subst (norm1,t1) (norm2,t2) = (*D*) inside 'F'; try let rc = - pp (lazy(" " ^ ppterm ~metasenv ~subst ~context t1 ^ " ==?== " ^ + pp (lazy(" " ^ ppterm ~metasenv ~subst ~context t1 ^ + (if swap then " ==>?== " + else " ==??== " + else " == prerr_endline "Appl [Appl _;_] or Appl [] or Appl [_] invariant"; assert false - | (C.Sort (C.Type a), C.Sort (C.Type b)) when not test_eq_only -> + | (C.Sort (C.Type a), C.Sort (C.Type b)) when not test_eq_only -> + let a, b = if swap then b,a else a,b in if NCicEnvironment.universe_leq a b then metasenv, subst 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 (UnificationFailure (mk_msg metasenv subst context t1 t2)) - | (C.Sort C.Prop,C.Sort (C.Type _)) -> + | (C.Sort C.Prop,C.Sort (C.Type _)) when not swap -> + if (not test_eq_only) then metasenv, subst + else raise (UnificationFailure (mk_msg metasenv subst context t1 t2)) + | (C.Sort (C.Type _), C.Sort C.Prop) when swap -> if (not test_eq_only) then metasenv, subst 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 metasenv, subst = unify rdb true metasenv subst context s1 s2 in - unify rdb test_eq_only metasenv subst ((name1, C.Decl s1)::context) t1 t2 + let metasenv, subst = unify rdb true metasenv subst context s1 s2 swap in + unify rdb test_eq_only metasenv subst ((name1, C.Decl s1)::context) t1 t2 swap | (C.LetIn (name1,ty1,s1,t1), C.LetIn(_,ty2,s2,t2)) -> - let metasenv,subst=unify rdb test_eq_only metasenv subst context ty1 ty2 in - let metasenv,subst=unify rdb test_eq_only metasenv subst context s1 s2 in + let metasenv,subst=unify rdb test_eq_only metasenv subst context ty1 ty2 swap in + let metasenv,subst=unify rdb test_eq_only metasenv subst context s1 s2 swap in let context = (name1, C.Def (s1,ty1))::context in - unify rdb test_eq_only metasenv subst context t1 t2 + unify rdb test_eq_only metasenv subst context t1 t2 swap | (C.Meta (n1,(s1,l1 as lc1)),C.Meta (n2,(s2,l2 as lc2))) when n1 = n2 -> (try @@ -444,8 +452,9 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = (fun t1 t2 (metasenv, subst, to_restrict, i) -> try let metasenv, subst = - unify rdb test_eq_only metasenv subst context + unify rdb (*test_eq_only*) true metasenv subst context (NCicSubstitution.lift s1 t1) (NCicSubstitution.lift s2 t2) + swap in metasenv, subst, to_restrict, i-1 with UnificationFailure _ | Uncertain _ -> @@ -465,7 +474,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let _,_,term,_ = NCicUtils.lookup_subst n1 subst in let term1 = NCicSubstitution.subst_meta lc1 term in let term2 = NCicSubstitution.subst_meta lc2 term in - unify rdb test_eq_only metasenv subst context term1 term2 + unify rdb test_eq_only metasenv subst context term1 term2 swap with NCicUtils.Subst_not_found _-> raise (UnificationFailure msg)) | NCic.Appl (NCic.Meta (i,_)::_ as l1), @@ -473,12 +482,13 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = (try List.fold_left2 (fun (metasenv, subst) t1 t2 -> - unify rdb test_eq_only metasenv subst context t1 t2) + unify rdb (*test_eq_only*) true metasenv subst context t1 + t2 swap) (metasenv,subst) l1 l2 with Invalid_argument _ -> raise (UnificationFailure (mk_msg metasenv subst context t1 t2))) - | _, NCic.Meta (n, _) when is_locked n subst -> + | _, NCic.Meta (n, _) when is_locked n subst && not swap-> (let (metasenv, subst), i = match NCicReduction.whd ~subst context t1 with | NCic.Appl (NCic.Meta (i,l) as meta :: args) -> @@ -487,7 +497,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = (NCicTypeChecker.typeof ~metasenv ~subst context meta) in unify rdb test_eq_only metasenv subst context - (C.Meta (i,l)) lambda_Mj, + (C.Meta (i,l)) lambda_Mj false, i | NCic.Meta (i,_) -> (metasenv, subst), i | _ -> @@ -518,36 +528,30 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let subst = List.filter (fun (j,_) -> j <> i) subst in metasenv, ((i, (name, ctx, term, ty)) :: subst) with Not_found -> assert 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 + | NCic.Meta (n, _), _ when is_locked n subst && swap -> + unify rdb test_eq_only metasenv subst context t2 t1 false | 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 - let term = NCicSubstitution.subst_meta l term in - unify rdb test_eq_only metasenv subst context - (mk_appl ~upto:(List.length args) term args) t2 + unify rdb test_eq_only metasenv subst context t term swap + | C.Meta (n,_), _ when List.mem_assoc n subst -> + unify rdb test_eq_only metasenv subst context t2 t1 (not swap) | _, NCic.Appl (NCic.Meta (i,l)::args) when List.mem_assoc i subst -> let _,_,term,_ = NCicUtils.lookup_subst i subst in let term = NCicSubstitution.subst_meta l term in unify rdb test_eq_only metasenv subst context t1 - (mk_appl ~upto:(List.length args) term args) + (mk_appl ~upto:(List.length args) term args) swap + | NCic.Appl (NCic.Meta (i,_)::_), _ when List.mem_assoc i subst -> + unify rdb test_eq_only metasenv subst context t2 t1 (not swap) | C.Meta (n,lc), t -> instantiate rdb test_eq_only metasenv subst context n lc - (NCicReduction.head_beta_reduce ~subst t) false - + (NCicReduction.head_beta_reduce ~subst t) swap | t, C.Meta (n,lc) -> instantiate rdb test_eq_only metasenv subst context n lc - (NCicReduction.head_beta_reduce ~subst t) true + (NCicReduction.head_beta_reduce ~subst t) (not swap) | NCic.Appl (NCic.Meta (i,l) as meta :: args), _ -> let metasenv, lambda_Mj = @@ -557,13 +561,13 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let metasenv, subst = try unify rdb test_eq_only metasenv subst context - (C.Meta (i,l)) lambda_Mj + (C.Meta (i,l)) lambda_Mj swap with UnificationFailure msg | Uncertain msg when not norm2-> (* 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 + unify rdb test_eq_only metasenv subst context t1 t2 swap in (try let name, ctx, term, ty = NCicUtils.lookup_subst i subst in @@ -571,29 +575,8 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let subst = List.filter (fun (j,_) -> j <> i) subst in metasenv, ((i, (name, ctx, term, ty)) :: subst) with Not_found -> assert false) - - | _, NCic.Appl (NCic.Meta (i,l) as meta :: args) -> - let metasenv, lambda_Mj = - lambda_intros rdb metasenv subst context (List.length args) - (NCicTypeChecker.typeof ~metasenv ~subst context meta) - in - let metasenv, subst = - try - unify rdb test_eq_only metasenv subst context - lambda_Mj (C.Meta (i,l)) - with UnificationFailure msg | Uncertain msg when not norm1 -> - (* 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 - (try - let name, ctx, term, ty = NCicUtils.lookup_subst i subst in - let term = eta_reduce subst term in - let subst = List.filter (fun (j,_) -> j <> i) subst in - metasenv, ((i, (name, ctx, term, ty)) :: subst) - with Not_found -> assert false) + | _, NCic.Appl (NCic.Meta (_,_) :: _) -> + unify rdb test_eq_only metasenv subst context t2 t1 (not swap) (* processing this case here we avoid a useless small delta step *) | (C.Appl ((C.Const r1) as _hd1::tl1), C.Appl (C.Const r2::tl2)) @@ -607,6 +590,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = match relevance with b::tl -> b,tl | _ -> true, [] in let metasenv, subst = try unify rdb test_eq_only metasenv subst context t1 t2 + swap with UnificationFailure _ | Uncertain _ when not b -> metasenv, subst in @@ -642,16 +626,16 @@ and unify rdb test_eq_only 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 + unify rdb test_eq_only metasenv subst context outtype1 outtype2 swap in let metasenv, subst = - try unify rdb test_eq_only metasenv subst context term1 term2 + try unify rdb test_eq_only metasenv subst context term1 term2 swap with UnificationFailure _ | Uncertain _ when is_prop -> metasenv, subst in (try List.fold_left2 - (fun (metasenv,subst) -> - unify rdb test_eq_only metasenv subst context) + (fun (metasenv,subst) t1 t2 -> + unify rdb test_eq_only metasenv subst context t1 t2 swap) (metasenv, subst) pl1 pl2 with Invalid_argument _ -> assert false) | (C.Implicit _, _) | (_, C.Implicit _) -> assert false @@ -692,7 +676,7 @@ and unify rdb test_eq_only metasenv subst context t1 t2 = let metasenv,subst = List.fold_left (fun (metasenv, subst) (x,y) -> - unify rdb test_eq_only metasenv subst context x y) + unify rdb test_eq_only metasenv subst context x y false) (metasenv, subst) premises in pp(lazy("FUNZIONA!")); @@ -824,7 +808,7 @@ and delift_type_wrt_terms rdb metasenv subst context t args = ~unify:(fun m s c t1 t2 -> let ind = !indent in let res = - try Some (unify rdb false m s c t1 t2 ) + try Some (unify rdb false m s c t1 t2 false) with UnificationFailure _ | Uncertain _ -> None in indent := ind; res) @@ -837,9 +821,9 @@ and delift_type_wrt_terms rdb metasenv subst context t args = ;; -let unify rdb ?(test_eq_only=false) = +let unify rdb ?(test_eq_only=false) ?(swap=false) metasenv subst context t1 t2= indent := ""; - unify rdb test_eq_only;; + unify rdb test_eq_only metasenv subst context t1 t2 swap;; let fix_sorts m s = fix m s true false (UnificationFailure (lazy "no sup")) diff --git a/helm/software/components/ng_refiner/nCicUnification.mli b/helm/software/components/ng_refiner/nCicUnification.mli index 954f56e58..429610218 100644 --- a/helm/software/components/ng_refiner/nCicUnification.mli +++ b/helm/software/components/ng_refiner/nCicUnification.mli @@ -18,6 +18,7 @@ exception AssertFailure of string Lazy.t;; val unify : #NRstatus.status -> ?test_eq_only:bool -> (* default: false *) + ?swap:bool -> (* default: false *) NCic.metasenv -> NCic.substitution -> NCic.context -> NCic.term -> NCic.term -> NCic.metasenv * NCic.substitution