\ / GNU General Public License Version 2
V_____________________________________________________________*)
-include "turing/multi_universal/moves_2.ma".
-include "turing/multi_universal/match.ma".
-include "turing/multi_universal/copy.ma".
+include "turing/auxiliary_machines.ma".
+include "turing/auxiliary_multi_machines.ma".
include "turing/multi_universal/alphabet.ma".
include "turing/multi_universal/tuples.ma".
-(*
-
- in.obj : ... x ...
- ^
- in.cfg : ... ? ? ...
- ^
-
- out.cfg : ... 1 x ...
- ^
-
- ---------------------
- current (in.obj) = None
-
- in.cfg : ... ? ? ...
- ^
-
- out.cfg : ... 0 0 ...
- ^
-
- obj_to_cfg ≝
- move_l(cfg);
- move_l(cfg);
- (if (current(in.obj)) == None
- then write(0,cfg);
- move_r(cfg);
- write(0,cfg);
- else write(1,cfg);
- move_r(cfg);
- copy_step(obj,cfg);
- move_l(obj);)
- move_to_end_l(cfg);
- move_r(cfg);
-
-
- cfg_to_obj
-*)
definition obj ≝ (0:DeqNat).
definition cfg ≝ (1:DeqNat).
definition prg ≝ (2:DeqNat).
definition obj_to_cfg ≝
- mmove cfg FSUnialpha 2 L ·
(ifTM ?? (inject_TM ? (test_null ?) 2 obj)
- (copy_step obj cfg FSUnialpha 2 ·
- mmove cfg FSUnialpha 2 L ·
- mmove obj FSUnialpha 2 L)
+ (copy_char_N obj cfg FSUnialpha 2)
(inject_TM ? (write FSUnialpha null) 2 cfg)
tc_true) ·
inject_TM ? (move_to_end FSUnialpha L) 2 cfg ·
definition R_obj_to_cfg ≝ λt1,t2:Vector (tape FSUnialpha) 3.
∀c,ls.
- nth cfg ? t1 (niltape ?) = mk_tape FSUnialpha (c::ls) (None ?) [ ] →
+ nth cfg ? t1 (niltape ?) = midtape ? ls c [ ] →
(∀lso,x,rso.nth obj ? t1 (niltape ?) = midtape FSUnialpha lso x rso →
t2 = change_vec ?? t1
(mk_tape ? [ ] (option_hd ? (reverse ? (x::ls))) (tail ? (reverse ? (x::ls)))) cfg) ∧
t2 = change_vec ?? t1
(mk_tape ? [ ] (option_hd FSUnialpha (reverse ? (null::ls)))
(tail ? (reverse ? (null::ls)))) cfg).
-
-axiom sem_move_to_end_l : ∀sig. move_to_end sig L ⊨ R_move_to_end_l sig.
+
+(*
axiom accRealize_to_Realize :
∀sig,n.∀M:mTM sig n.∀Rtrue,Rfalse,acc.
M ⊨ [ acc: Rtrue, Rfalse ] → M ⊨ Rtrue ∪ Rfalse.
+*)
lemma eq_mk_tape_rightof :
∀alpha,a,al.mk_tape alpha (a::al) (None ?) [ ] = rightof ? a al.
#alpha #a #al %
qed.
-axiom daemon : ∀P:Prop.P.
-
-definition option_cons ≝ λsig.λc:option sig.λl.
- match c with [ None ⇒ l | Some c0 ⇒ c0::l ].
-
lemma tape_move_mk_tape_R :
∀sig,ls,c,rs.
(c = None ? → ls = [ ] ∨ rs = [ ]) →
normalize //
qed.
+lemma None_or_Some: ∀A.∀a. a =None A ∨ ∃b. a = Some ? b.
+#A * /2/ #a %2 %{a} %
+qed.
+
+lemma not_None_to_Some: ∀A.∀a. a ≠ None A → ∃b. a = Some ? b.
+#A * /2/ * #H @False_ind @H %
+qed.
+
lemma sem_obj_to_cfg : obj_to_cfg ⊨ R_obj_to_cfg.
-@(sem_seq_app FSUnialpha 2 ????? (sem_move_multi ? 2 cfg L ?)
- (sem_seq ??????
- (sem_if ??????????
- (sem_test_null_multi ?? obj ?)
- (sem_seq ?????? (accRealize_to_Realize … (sem_copy_step …))
- (sem_seq ?????? (sem_move_multi ? 2 cfg L ?)
- (sem_move_multi ? 2 obj L ?)))
- (sem_inject ???? cfg ? (sem_write FSUnialpha null)))
- (sem_seq ?????? (sem_inject ???? cfg ? (sem_move_to_end_l ?))
- (sem_move_multi ? 2 cfg R ?)))) //
-#ta #tb *
-#tc * whd in ⊢ (%→?); #Htc *
-#td * *
-[ * #te * * #Hcurtc #Hte
- * destruct (Hte) #te * *
- [ whd in ⊢ (%→%→?); * #x * #y * * -Hcurtc #Hcurtc1 #Hcurtc2 #Hte
- * #tf * whd in ⊢ (%→%→?); #Htf #Htd
- * #tg * * * whd in ⊢ (%→%→%→%→?); #Htg1 #Htg2 #Htg3 #Htb
- #c #ls #Hta1 %
- [ #lso #x0 #rso #Hta2 >Hta1 in Htc; >eq_mk_tape_rightof
- whd in match (tape_move ???); #Htc
- cut (tg = change_vec ?? td (mk_tape ? [ ] (None ?) (reverse ? ls@[x])) cfg)
- [@daemon] -Htg1 -Htg2 -Htg3 #Htg destruct (Htg Htf Hte Htd Htc Htb)
- >change_vec_change_vec >change_vec_change_vec
- >change_vec_commute // >change_vec_change_vec
- >change_vec_commute [|@sym_not_eq //] >change_vec_change_vec
- >change_vec_commute // >change_vec_change_vec
- >nth_change_vec // >nth_change_vec_neq [|@sym_not_eq //]
- >nth_change_vec // >nth_change_vec_neq [|@sym_not_eq //]
- >change_vec_commute [|@sym_not_eq //] @eq_f3 //
- [ >Hta2 cases rso in Hta2; whd in match (tape_move_mono ???);
- [ #Hta2 whd in match (tape_move ???); <Hta2 @change_vec_same
- | #r1 #rs1 #Hta2 whd in match (tape_move ???); <Hta2 @change_vec_same ]
- | >tape_move_mk_tape_R [| #_ % %] >reverse_cons
- >nth_change_vec_neq in Hcurtc1; [|@sym_not_eq //] >Hta2
- normalize in ⊢ (%→?); #H destruct (H) %
- ]
- | #Hta2 >Htc in Hcurtc1; >nth_change_vec_neq [| @sym_not_eq //]
- >Hta2 #H destruct (H)
+@(sem_seq_app FSUnialpha 2 ?????
+ (sem_if ??????????
+ (sem_test_null_multi ?? obj ?)
+ (sem_copy_char_N …)
+ (sem_inject ???? cfg ? (sem_write FSUnialpha null)))
+ (sem_seq ?????? (sem_inject ???? cfg ? (sem_move_to_end_l ?))
+ (sem_move_multi ? 2 cfg R ?))) //
+#ta #tout *
+#tb * #Hif * #tc * #HM2 #HM3 #c #ls #Hcfg
+(* Hif *)
+cases Hif -Hif
+[ * #t1 * * #Hcurta #Ht1 destruct (Ht1)
+ lapply (not_None_to_Some … Hcurta) * #curta #Hcurtaeq
+ whd in ⊢ (%→?); #Htb % [2: #Hcur @False_ind /2/]
+ #lso #xo #rso #Hobjta cases HM2 whd in ⊢ (%→?); * #_
+ #HM2 #Heq >Htb in HM2; >nth_change_vec [2: @leb_true_to_le %]
+ >Hcfg >Hcurtaeq #HM2 lapply (HM2 … (refl ??)) -HM2
+ whd in match (left ??); whd in match (right ??);
+ >reverse_cons #Htc >HM3 @(eq_vec … (niltape ?)) #i #lei2
+ cases (le_to_or_lt_eq … (le_S_S_to_le …lei2))
+ [#lei1 cases (le_to_or_lt_eq … (le_S_S_to_le …lei1))
+ [#lei0 lapply(le_n_O_to_eq … (le_S_S_to_le …lei0)) #eqi <eqi
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ <(Heq 0) [2:@eqb_false_to_not_eq %] >Htb
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [%|2:@eqb_false_to_not_eq %]
+ |#Hi >Hi >nth_change_vec // >nth_change_vec // >Htc
+ >Hobjta in Hcurtaeq; whd in ⊢ (??%?→?); #Htmp destruct(Htmp)
+ >tape_move_mk_tape_R [2: #_ %1 %] %
]
- | * #Hcurtc0 #Hte #_ #_ #c #ls #Hta1 >Hta1 in Htc; >eq_mk_tape_rightof
- whd in match (tape_move ???); #Htc >Htc in Hcurtc0; *
- [ >Htc in Hcurtc; >nth_change_vec_neq [|@sym_not_eq //]
- #Hcurtc #Hcurtc0 >Hcurtc0 in Hcurtc; * #H @False_ind @H %
- | >nth_change_vec // normalize in ⊢ (%→?); #H destruct (H) ]
+ |#Hi >Hi >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ <(Heq 2) [2:@eqb_false_to_not_eq %] >Htb
+ >nth_change_vec_neq [%|2:@eqb_false_to_not_eq %]
+ ]
+| * #t1 * * #Hcurta #Ht1 destruct (Ht1)
+ * whd in ⊢ (%→?); #Htb lapply (Htb … Hcfg) -Htb #Htb
+ #Htbeq %
+ [#lso #xo #rso #Hmid @False_ind >Hmid in Hcurta;
+ whd in ⊢ (??%?→?); #Htmp destruct (Htmp)]
+ #_ cases HM2 whd in ⊢ (%→?); * #_
+ #HM2 #Heq >Htb in HM2; #HM2 lapply (HM2 … (refl ??)) -HM2
+ #Htc >HM3 @(eq_vec … (niltape ?)) #i #lei2
+ cases (le_to_or_lt_eq … (le_S_S_to_le …lei2))
+ [#lei1 cases (le_to_or_lt_eq … (le_S_S_to_le …lei1))
+ [#lei0 lapply(le_n_O_to_eq … (le_S_S_to_le …lei0)) #eqi <eqi
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ <(Heq 0) [2:@eqb_false_to_not_eq %] >Htb
+ <(Htbeq 0) [2:@eqb_false_to_not_eq %] %
+ |#Hi >Hi >nth_change_vec // >nth_change_vec // >Htc
+ >tape_move_mk_tape_R [2: #_ %1 %] >reverse_cons %
+ ]
+ |#Hi >Hi >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ <(Heq 2) [2:@eqb_false_to_not_eq %]
+ <(Htbeq 2) [%|@eqb_false_to_not_eq %]
]
-| * #te * * #Hcurtc #Hte
- * whd in ⊢ (%→%→?); #Htd1 #Htd2
- * #tf * * * #Htf1 #Htf2 #Htf3 whd in ⊢ (%→?); #Htb
- #c #ls #Hta1 %
- [ #lso #x #rso #Hta2 >Htc in Hcurtc; >nth_change_vec_neq [|@sym_not_eq //]
- >Hta2 normalize in ⊢ (%→?); #H destruct (H)
- | #_ >Hta1 in Htc; >eq_mk_tape_rightof whd in match (tape_move ???); #Htc
- destruct (Hte) cut (td = change_vec ?? tc (midtape ? ls null []) cfg)
- [@daemon] -Htd1 -Htd2 #Htd
- -Htf1 cut (tf = change_vec ?? td (mk_tape ? [ ] (None ?) (reverse ? ls@[null])) cfg)
- [@daemon] -Htf2 -Htf3 #Htf destruct (Htf Htd Htc Htb)
- >change_vec_change_vec >change_vec_change_vec >change_vec_change_vec
- >change_vec_change_vec >change_vec_change_vec >nth_change_vec //
- >reverse_cons >tape_move_mk_tape_R /2/ ]
]
qed.
+(* another semantics for obj_to_cfg *)
+definition low_char' ≝ λc.
+ match c with
+ [ None ⇒ null
+ | Some b ⇒ if (is_bit b) then b else null
+ ].
+
+lemma low_char_option : ∀s.
+ low_char' (option_map FinBool FSUnialpha bit s) = low_char s.
+* //
+qed.
+
+definition R_obj_to_cfg1 ≝ λt1,t2:Vector (tape FSUnialpha) 3.
+ ∀c,ls.
+ nth cfg ? t1 (niltape ?) = midtape ? ls c [ ] →
+ let x ≝ current ? (nth obj ? t1 (niltape ?)) in
+ (∀b. x= Some ? b → is_bit b = true) →
+ t2 = change_vec ?? t1
+ (mk_tape ? [ ] (option_hd FSUnialpha (reverse ? (low_char' x::ls)))
+ (tail ? (reverse ? (low_char' x::ls)))) cfg.
+
+lemma sem_obj_to_cfg1: obj_to_cfg ⊨ R_obj_to_cfg1.
+@(Realize_to_Realize … sem_obj_to_cfg) #t1 #t2 #Hsem
+#c #ls #Hcfg lapply(Hsem c ls Hcfg) * #HSome #HNone #Hb
+cases (None_or_Some ? (current ? (nth obj ? t1 (niltape ?))))
+ [#Hcur >Hcur @HNone @Hcur
+ |* #b #Hb1 >Hb1
+ cut (low_char' (Some ? b) = b) [whd in ⊢ (??%?); >(Hb b Hb1) %] #Hlow >Hlow
+ lapply(current_to_midtape … Hb1) * #lsobj * #rsobj #Hmid
+ @(HSome … Hmid)
+ ]
+qed.
+
+(* test_null_char *)
definition test_null_char ≝ test_char FSUnialpha (λc.c == null).
definition R_test_null_char_true ≝ λt1,t2.
mmove cfg FSUnialpha 2 L ·
(ifTM ?? (inject_TM ? test_null_char 2 cfg)
(nop ? 2)
- (copy_step cfg obj FSUnialpha 2 ·
- mmove cfg FSUnialpha 2 L ·
- mmove obj FSUnialpha 2 L)
- tc_true) ·
+ (copy_char_N cfg obj FSUnialpha 2)
+ tc_true).
+(* ·
inject_TM ? (move_to_end FSUnialpha L) 2 cfg ·
- mmove cfg FSUnialpha 2 R.
+ mmove cfg FSUnialpha 2 R. *)
definition R_cfg_to_obj ≝ λt1,t2:Vector (tape FSUnialpha) 3.
∀c,ls.
nth cfg ? t1 (niltape ?) = mk_tape FSUnialpha (c::ls) (None ?) [ ] →
- (c = null →
- t2 = change_vec ?? t1
- (mk_tape ? [ ] (option_hd FSUnialpha (reverse ? (c::ls)))
- (tail ? (reverse ? (c::ls)))) cfg) ∧
+ (c = null → t2 = change_vec ?? t1 (midtape ? ls c [ ]) cfg) ∧
(c ≠ null →
t2 = change_vec ??
(change_vec ?? t1
(midtape ? (left ? (nth obj ? t1 (niltape ?))) c (right ? (nth obj ? t1 (niltape ?)))) obj)
- (mk_tape ? [ ] (option_hd ? (reverse ? (c::ls))) (tail ? (reverse ? (c::ls)))) cfg).
+ (midtape ? ls c [ ]) cfg).
+
+lemma tape_move_mk_tape_L :
+ ∀sig,ls,c,rs.
+ (c = None ? → ls = [ ] ∨ rs = [ ]) →
+ tape_move ? (mk_tape sig ls c rs) L =
+ mk_tape ? (tail ? ls) (option_hd ? ls) (option_cons ? c rs).
+#sig * [ * [ * | #c * ] | #l0 #ls0 * [ *
+[| #r0 #rs0 #H @False_ind cases (H (refl ??)) #H1 destruct (H1) ] | #c * ] ]
+normalize //
+qed.
-axiom sem_cfg_to_obj : cfg_to_obj ⊨ R_cfg_to_obj.
-(*@(sem_seq_app FSUnialpha 2 ????? (sem_move_multi ? 2 cfg L ?)
- (sem_seq ??????
- (sem_if ??????????
- (sem_test_null_multi ?? obj ?)
- (sem_seq ?????? (accRealize_to_Realize … (sem_copy_step …))
- (sem_move_multi ? 2 cfg L ?))
- (sem_inject ???? cfg ? (sem_write FSUnialpha null)))
- (sem_seq ?????? (sem_inject ???? cfg ? (sem_move_to_end_l ?))
- (sem_move_multi ? 2 cfg R ?)))) //
+lemma sem_cfg_to_obj : cfg_to_obj ⊨ R_cfg_to_obj.
+@(sem_seq_app FSUnialpha 2 ????? (sem_move_multi ? 2 cfg L ?)
+ (sem_if ??????????
+ (acc_sem_inject ?????? cfg ? sem_test_null_char)
+ (sem_nop …)
+ (sem_copy_char_N …)))
+// [@sym_not_eq //]
#ta #tb *
#tc * whd in ⊢ (%→?); #Htc *
-#td * *
-[ * #te * * #Hcurtc #Hte
- * destruct (Hte) #te * *
- [ whd in ⊢ (%→%→?); * #x * #y * * -Hcurtc #Hcurtc1 #Hcurtc2 #Hte #Htd
- * #tf * * * whd in ⊢ (%→%→%→%→?); #Htf1 #Htf2 #Htf3 #Htb
- #c #ls #Hta1 %
- [ #lso #x0 #rso #Hta2 >Hta1 in Htc; >eq_mk_tape_rightof
- whd in match (tape_move ???); #Htc
- cut (tf = change_vec ?? tc (mk_tape ? [ ] (None ?) (reverse ? ls@[x])) cfg)
- [@daemon] -Htf1 -Htf2 -Htf3 #Htf destruct (Htf Hte Htd Htc Htb)
- >change_vec_change_vec >change_vec_change_vec >change_vec_change_vec
- >nth_change_vec // >tape_move_mk_tape_R
- @daemon
- | #Hta2 >Htc in Hcurtc1; >nth_change_vec_neq [| @sym_not_eq //]
- >Hta2 #H destruct (H)
- ]
- | * #Hcurtc0 #Hte #_ #_ #c #ls #Hta1 >Hta1 in Htc; >eq_mk_tape_rightof
- whd in match (tape_move ???); #Htc >Htc in Hcurtc0; *
- [ >Htc in Hcurtc; >nth_change_vec_neq [|@sym_not_eq //]
- #Hcurtc #Hcurtc0 >Hcurtc0 in Hcurtc; * #H @False_ind @H %
- | >nth_change_vec // normalize in ⊢ (%→?); #H destruct (H) ]
+[ * #te * * * #Hcurtc #Hte1 #Hte2 whd in ⊢ (%→?); #Htb destruct (Htb)
+ #c #ls #Hta %
+ [ #Hc >Hta in Htc; >eq_mk_tape_rightof whd in match (tape_move ???); #Htc
+ cut (te = tc)
+ [ lapply (eq_vec_change_vec ??????? (sym_eq … Hte1) Hte2) >change_vec_same // ]
+ -Hte1 -Hte2 #Hte //
+ | #Hc >Hta in Htc; >eq_mk_tape_rightof whd in match (tape_move ???); #Htc
+ >Htc in Hcurtc; >nth_change_vec // normalize in ⊢ (%→?);
+ #H destruct (H) @False_ind cases Hc /2/ ]
+| * #te * * * #Hcurtc #Hte1 #Hte2
+ whd in ⊢ (%→?); #Htb
+ #c #ls #Hta % #Hc
+ [ >Htc in Hcurtc; >Hta >nth_change_vec //
+ normalize in ⊢ (%→?); * #H @False_ind /2/
+ | cut (te = tc)
+ [ lapply (eq_vec_change_vec ??????? (sym_eq … Hte1) Hte2)
+ >change_vec_same // ] -Hte1 -Hte2 #Hte destruct (Hte)
+ >Hta in Htc; whd in match (tape_move ???); #Htc
+ >Htc in Htb; >nth_change_vec //
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq //] >Hta
+ #Htb @Htb
]
-| * #te * * #Hcurtc #Hte
- * whd in ⊢ (%→%→?); #Htd1 #Htd2
- * #tf * * * #Htf1 #Htf2 #Htf3 whd in ⊢ (%→?); #Htb
- #c #ls #Hta1 %
- [ #lso #x #rso #Hta2 >Htc in Hcurtc; >nth_change_vec_neq [|@sym_not_eq //]
- >Hta2 normalize in ⊢ (%→?); #H destruct (H)
- | #_ >Hta1 in Htc; >eq_mk_tape_rightof whd in match (tape_move ???); #Htc
- destruct (Hte) cut (td = change_vec ?? tc (midtape ? ls null []) cfg)
- [@daemon] -Htd1 -Htd2 #Htd
- -Htf1 cut (tf = change_vec ?? td (mk_tape ? [ ] (None ?) (reverse ? ls@[null])) cfg)
- [@daemon] -Htf2 -Htf3 #Htf destruct (Htf Htd Htc Htb)
- >change_vec_change_vec >change_vec_change_vec >change_vec_change_vec
- >change_vec_change_vec >change_vec_change_vec >nth_change_vec //
- >reverse_cons >tape_move_mk_tape_R /2/ ]
-]
qed.
-*)
-
-(* macchina che muove il nastro obj a destra o sinistra a seconda del valore
- del current di prg, che codifica la direzione in cui ci muoviamo *)
definition char_to_move ≝ λc.match c with
[ bit b ⇒ if b then R else L
| _ ⇒ N].
-
+
+definition char_to_bit_option ≝ λc.match c with
+ [ bit b ⇒ Some ? (bit b)
+ | _ ⇒ None ?].
+
+definition R_cfg_to_obj1 ≝ λt1,t2:Vector (tape FSUnialpha) 3.
+ ∀c,ls.
+ nth cfg ? t1 (niltape ?) = mk_tape FSUnialpha (c::ls) (None ?) [ ] →
+ c ≠ bar →
+ let new_obj ≝
+ tape_write ? (nth obj ? t1 (niltape ?)) (char_to_bit_option c) in
+ t2 = change_vec ??
+ (change_vec ?? t1
+ (tape_write ? (nth obj ? t1 (niltape ?)) (char_to_bit_option c)) obj)
+ (midtape ? ls c [ ]) cfg.
+
+lemma sem_cfg_to_obj1: cfg_to_obj ⊨ R_cfg_to_obj1.
+@(Realize_to_Realize … sem_cfg_to_obj) #t1 #t2 #H #c #ls #Hcfg #Hbar
+cases (H c ls Hcfg) cases (true_or_false (c==null)) #Hc
+ [#Ht2 #_ >(Ht2 (\P Hc)) -Ht2 @(eq_vec … (niltape ?))
+ #i #lei2 cases (le_to_or_lt_eq … (le_S_S_to_le …lei2))
+ [#lei1 cases (le_to_or_lt_eq … (le_S_S_to_le …lei1))
+ [#lei0 lapply(le_n_O_to_eq … (le_S_S_to_le …lei0)) #eqi <eqi
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq in ⊢ (???%); [2:@eqb_false_to_not_eq %]
+ >nth_change_vec // >(\P Hc) %
+ |#Hi >Hi >nth_change_vec //
+ ]
+ |#Hi >Hi >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %] %
+ ]
+ |#_ #Ht2 >(Ht2 (\Pf Hc)) -Ht2 @(eq_vec … (niltape ?))
+ #i #lei2 cases (le_to_or_lt_eq … (le_S_S_to_le …lei2))
+ [#lei1 cases (le_to_or_lt_eq … (le_S_S_to_le …lei1))
+ [#lei0 lapply(le_n_O_to_eq … (le_S_S_to_le …lei0)) #eqi <eqi
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq in ⊢ (???%); [2:@eqb_false_to_not_eq %]
+ >nth_change_vec // >nth_change_vec //
+ lapply (\bf Hbar) lapply Hc elim c //
+ [whd in ⊢ (??%?→?); #H destruct (H)
+ |#_ whd in ⊢ (??%?→?); #H destruct (H)
+ ]
+ |#Hi >Hi >nth_change_vec //
+ ]
+ |#Hi >Hi >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %]
+ >nth_change_vec_neq [2:@eqb_false_to_not_eq %] %
+ ]
+ ]
+qed.
+
+
+(* macchina che muove il nastro obj a destra o sinistra a seconda del valore
+ del current di prg, che codifica la direzione in cui ci muoviamo *)
+
definition tape_move_obj : mTM FSUnialpha 2 ≝
ifTM ??
(inject_TM ? (test_char ? (λc:FSUnialpha.c == bit false)) 2 prg)
tc_true)
tc_true.
-definition restart_tape ≝ λi.
- inject_TM ? (move_to_end FSUnialpha L) 2 i ·
- mmove i FSUnialpha 2 R.
-
-definition unistep ≝
- match_m cfg prg FSUnialpha 2 ·
- restart_tape cfg · copy prg cfg FSUnialpha 2 ·
- cfg_to_obj · tape_move_obj · restart_tape prg · obj_to_cfg.
+definition R_tape_move_obj' ≝ λt1,t2:Vector (tape FSUnialpha) 3.
+ (current ? (nth prg ? t1 (niltape ?)) = Some ? (bit false) →
+ t2 = change_vec ?? t1 (tape_move ? (nth obj ? t1 (niltape ?)) L) obj) ∧
+ (current ? (nth prg ? t1 (niltape ?)) = Some ? (bit true) →
+ t2 = change_vec ?? t1 (tape_move ? (nth obj ? t1 (niltape ?)) R) obj) ∧
+ (current ? (nth prg ? t1 (niltape ?)) ≠ Some ? (bit false) →
+ current ? (nth prg ? t1 (niltape ?)) ≠ Some ? (bit true) →
+ t2 = t1).
+
+lemma sem_tape_move_obj' : tape_move_obj ⊨ R_tape_move_obj'.
+#ta cases (sem_if ??????????
+ (acc_sem_inject ?????? prg ? (sem_test_char ? (λc:FSUnialpha.c == bit false)))
+ (sem_move_multi ? 2 obj L ?)
+ (sem_if ??????????
+ (acc_sem_inject ?????? prg ? (sem_test_char ? (λc:FSUnialpha.c == bit true)))
+ (sem_move_multi ? 2 obj R ?)
+ (sem_nop …)) ta) //
+#i * #outc * #Hloop #HR %{i} %{outc} % [@Hloop] -i
+cases HR -HR
+[ * #tb * * * * #c * #Hcurta_prg #Hc lapply (\P Hc) -Hc #Hc #Htb1 #Htb2
+ whd in ⊢ (%→%); #Houtc >Houtc -Houtc % [ %
+ [ >Hcurta_prg #H destruct (H) >(?:tb = ta)
+ [| lapply (eq_vec_change_vec ??????? Htb1 Htb2)
+ >change_vec_same // ] %
+ | >Hcurta_prg #H destruct (H) destruct (Hc) ]
+ | >Hcurta_prg >Hc * #H @False_ind /2/ ]
+| * #tb * * * #Hnotfalse #Htb1 #Htb2 cut (tb = ta)
+ [ lapply (eq_vec_change_vec ??????? Htb1 Htb2)
+ >change_vec_same // ] -Htb1 -Htb2 #Htb destruct (Htb) *
+ [ * #tc * * * * #c * #Hcurta_prg #Hc lapply (\P Hc) -Hc #Hc #Htc1 #Htc2
+ whd in ⊢ (%→%); #Houtc >Houtc -Houtc % [ %
+ [ >Hcurta_prg #H destruct (H) destruct (Hc)
+ | >Hcurta_prg #H destruct (H) >(?:tc = ta)
+ [| lapply (eq_vec_change_vec ??????? Htc1 Htc2)
+ >change_vec_same // ] % ]
+ | >Hcurta_prg >Hc #_ * #H @False_ind /2/ ]
+ | * #tc * * * #Hnottrue #Htc1 #Htc2 cut (tc = ta)
+ [ lapply (eq_vec_change_vec ??????? Htc1 Htc2)
+ >change_vec_same // ] -Htc1 -Htc2
+ #Htc destruct (Htc) whd in ⊢ (%→?); #Houtc % [ %
+ [ #Hcurta_prg lapply (\Pf (Hnotfalse ? Hcurta_prg)) * #H @False_ind /2/
+ | #Hcurta_prg lapply (\Pf (Hnottrue ? Hcurta_prg)) * #H @False_ind /2/ ]
+ | #_ #_ @Houtc ]
+ ]
+]
+qed.
-(*
-definition legal_tape ≝ λn,l,h,t.
- ∃state,char,table.
- nth cfg ? t1 (niltape ?) = midtape ? [ ] bar (state@[char]) →
- is_config n (bar::state@[char]) →
- nth prg ? t1 (niltape ?) = midtape ? [ ] bar table →
- bar::table = table_TM n l h → *)
+definition R_tape_move_obj ≝ λt1,t2:Vector (tape FSUnialpha) 3.
+ ∀c. current ? (nth prg ? t1 (niltape ?)) = Some ? c →
+ t2 = change_vec ?? t1 (tape_move ? (nth obj ? t1 (niltape ?)) (char_to_move c)) obj.
-definition list_of_tape ≝ λsig,t.
- left sig t@option_cons ? (current ? t) (right ? t).
+lemma sem_tape_move_obj : tape_move_obj ⊨ R_tape_move_obj.
+@(Realize_to_Realize … sem_tape_move_obj')
+#ta #tb * * #Htb1 #Htb2 #Htb3 * [ *
+[ @Htb2 | @Htb1 ]
+| #Hcurta_prg change with (nth obj ? ta (niltape ?)) in match (tape_move ???);
+ >change_vec_same @Htb3 >Hcurta_prg % #H destruct (H)
+| #Hcurta_prg change with (nth obj ? ta (niltape ?)) in match (tape_move ???);
+ >change_vec_same @Htb3 >Hcurta_prg % #H destruct (H)
+]
+qed.
-definition low_char' ≝ λc.
- match c with
- [ None ⇒ null
- | Some b ⇒ if (is_bit b) then b else null
- ].
-
-definition R_unistep ≝ λn,l,h.λt1,t2: Vector ? 3.
- ∀state,char,table.
- (* cfg *)
- nth cfg ? t1 (niltape ?) = midtape ? [ ] bar (state@[char]) →
- is_config n (bar::state@[char]) →
- (* prg *)
- nth prg ? t1 (niltape ?) = midtape ? [ ] bar table →
- bar::table = table_TM n l h →
- (* obj *)
- only_bits (list_of_tape ? (nth obj ? t1 (niltape ?))) →
- let conf ≝ (bar::state@[char]) in
- (∃ll,lr.bar::table = ll@conf@lr) →
- ∃nstate,nchar,m,t. tuple_encoding n h t = (conf@nstate@[nchar;m]) ∧
- mem ? t l ∧
- let new_obj ≝
- tape_move_mono ? (nth obj ? t1 (niltape ?))
- 〈Some ? nchar,char_to_move m〉 in
- let next_char ≝ low_char' (current ? new_obj) in
- t2 =
- change_vec ??
- (change_vec ?? t1 (midtape ? [ ] bar (nstate@[next_char])) cfg)
- new_obj obj.
+(************** list of tape ******************)
+definition list_of_tape ≝ λsig.λt:tape sig.
+ reverse ? (left ? t)@option_cons ? (current ? t) (right ? t).
-definition tape_map ≝ λA,B:FinSet.λf:A→B.λt.
- mk_tape B (map ?? f (left ? t))
- (option_map ?? f (current ? t))
- (map ?? f (right ? t)).
+lemma list_of_midtape: ∀sig,ls,c,rs.
+ list_of_tape sig (midtape ? ls c rs) = reverse ? ls@c::rs.
+// qed-.
-definition low_tapes ≝ λM:normalTM.λc:nconfig (no_states M).Vector_of_list ?
- [tape_map ?? bit (ctape ?? c);
- midtape ? [ ] bar (bits_of_state ? (nhalt M) (cstate ?? c));
- midtape ? [ ] bar (table_TM ? (graph_enum ?? (ntrans M)) (nhalt M))
- ].
+lemma list_of_rightof: ∀sig,ls,c.
+ list_of_tape sig (rightof ? c ls) = reverse ? (c::ls).
+#sig #ls #c <(append_nil ? (reverse ? (c::ls)))
+// qed-.
-definition R_unistep_high ≝ λM:normalTM.λc:nconfig (no_states M).λt1,t2.
- t1 = low_tapes M c →
- t2 = low_tapes M (step ? M c).
+lemma list_of_tape_move: ∀sig,t,m.
+ list_of_tape sig t = list_of_tape sig (tape_move ? t m).
+#sig #t * // cases t //
+ [(* rightof, move L *) #a #l >list_of_midtape
+ >append_cons <reverse_single <reverse_append %
+ |(* midtape, move L *) * //
+ #a #ls #c #rs >list_of_midtape >list_of_midtape
+ >reverse_cons >associative_append %
+ |(* midtape, move R *) #ls #c *
+ [>list_of_midtape >list_of_rightof >reverse_cons %
+ |#a #rs >list_of_midtape >list_of_midtape >reverse_cons
+ >associative_append %
+ ]
+ ]
+qed.
+lemma list_of_tape_write: ∀sig,cond,t,c.
+(∀b. c = Some ? b → cond b =true) →
+(∀x. mem ? x (list_of_tape ? t) → cond x =true ) →
+∀x. mem ? x (list_of_tape sig (tape_write ? t c)) → cond x =true.
+#sig #cond #t #c #Hc #Htape #x lapply Hc cases c
+ [(* c is None *) #_ whd in match (tape_write ???); @Htape
+ |#b #Hb lapply (Hb … (refl ??)) -Hb #Hb
+ whd in match (tape_write ???); >list_of_midtape
+ #Hx cases(mem_append ???? Hx) -Hx
+ [#Hx @Htape @mem_append_l1 @Hx
+ |* [//]
+ #Hx @Htape @mem_append_l2 cases (current sig t)
+ [@Hx | #c1 %2 @Hx]
+ ]
+ ]
+qed.
+
+lemma current_in_list: ∀sig,t,b.
+ current sig t = Some ? b → mem ? b (list_of_tape sig t).
+#sig #t #b cases t
+ [whd in ⊢ (??%?→?); #Htmp destruct
+ |#l #b whd in ⊢ (??%?→?); #Htmp destruct
+ |#l #b whd in ⊢ (??%?→?); #Htmp destruct
+ |#ls #c #rs whd in ⊢ (??%?→?); #Htmp destruct
+ >list_of_midtape @mem_append_l2 % %
+ ]
+qed.
+definition restart_tape ≝ λi,n.
+ mmove i FSUnialpha n L ·
+ inject_TM ? (move_to_end FSUnialpha L) n i ·
+ mmove i FSUnialpha n R.
-
\ No newline at end of file
+definition R_restart_tape ≝ λi,n.λint,outt:Vector (tape FSUnialpha) (S n).
+ ∀t.t = nth i ? int (niltape ?) →
+ outt = change_vec ?? int
+ (mk_tape ? [ ] (option_hd ? (list_of_tape ? t)) (tail ? (list_of_tape ? t))) i.
+
+lemma sem_restart_tape : ∀i,n.i < S n → restart_tape i n ⊨ R_restart_tape i n.
+#i #n #Hleq
+@(sem_seq_app ??????? (sem_move_multi ? n i L ?)
+ (sem_seq ?????? (sem_inject ???? i ? (sem_move_to_end_l ?))
+ (sem_move_multi ? n i R ?))) [1,2,3:@le_S_S_to_le //]
+#ta #tb * #tc * whd in ⊢ (%→?); #Htc
+* #td * * * #Htd1 #Htd2 #Htd3
+whd in ⊢ (%→?); #Htb *
+[ #Hta_i <Hta_i in Htc; whd in ⊢ (???(????%?)→?); #Htc
+ cut (td = tc)
+ [ <(change_vec_same … tc … i … (niltape ?))
+ @(eq_vec_change_vec … (niltape ?))
+ [ @Htd1 >Htc >nth_change_vec //
+ | @Htd3 ] ]
+ (* >Htc in Htd1; >nth_change_vec // *) -Htd1 -Htd2 -Htd3
+ #Htd >Htd in Htb; >Htc >change_vec_change_vec >nth_change_vec //
+ #Htb >Htb %
+| #r0 #rs0 #Hta_i <Hta_i in Htc; whd in ⊢ (???(????%?)→?); #Htc
+ cut (td = tc)
+ [ <(change_vec_same … tc … i … (niltape ?))
+ @(eq_vec_change_vec … (niltape ?))
+ [ @Htd1 >Htc >nth_change_vec //
+ | @Htd3 ] ]
+ (* >Htc in Htd1; >nth_change_vec // *) -Htd1 -Htd2 -Htd3
+ #Htd >Htd in Htb; >Htc >change_vec_change_vec >nth_change_vec //
+ #Htb >Htb %
+| #l0 #ls0 #Hta_i <Hta_i in Htc; whd in ⊢ (???(????%?)→?); #Htc
+ cut (td = change_vec ?? tc (mk_tape ? [ ] (None ?) (reverse ? ls0@[l0])) i)
+ [ <(change_vec_same … tc … i … (niltape ?))
+ @(eq_vec_change_vec … (niltape ?))
+ [ @Htd2 >Htc >nth_change_vec //
+ | #j #Hij >nth_change_vec_neq // @Htd3 // ]]
+ #Htd >Htd in Htb; >Htc >change_vec_change_vec >change_vec_change_vec
+ >nth_change_vec // #Htb >Htb <(reverse_reverse ? ls0) in ⊢ (???%);
+ cases (reverse ? ls0)
+ [ %
+ | #l1 #ls1 >reverse_cons
+ >(?: list_of_tape ? (rightof ? l0 (reverse ? ls1@[l1])) =
+ l1::ls1@[l0])
+ [|change with (reverse ??@?) in ⊢ (??%?);
+ whd in match (left ??); >reverse_cons >reverse_append
+ whd in ⊢ (??%?); @eq_f >reverse_reverse normalize >append_nil % ] % ]
+| *
+ [ #c #rs #Hta_i <Hta_i in Htc; whd in ⊢ (???(????%?)→?); #Htc
+ cut (td = tc)
+ [ <(change_vec_same … tc … i … (niltape ?))
+ @(eq_vec_change_vec … (niltape ?))
+ [ @Htd1 >Htc >nth_change_vec //
+ | @Htd3 ] ]
+ (* >Htc in Htd1; >nth_change_vec // *) -Htd1 -Htd2 -Htd3
+ #Htd >Htd in Htb; >Htc >change_vec_change_vec >nth_change_vec //
+ #Htb >Htb %
+ | #l0 #ls0 #c #rs #Hta_i <Hta_i in Htc; whd in ⊢ (???(????%?)→?); #Htc
+ cut (td = change_vec ?? tc (mk_tape ? [ ] (None ?) (reverse ? ls0@l0::c::rs)) i)
+ [ @(eq_vec_change_vec … (niltape ?))
+ [ @Htd2 >Htc >nth_change_vec //
+ | @Htd3 ] ]
+ #Htd >Htd in Htb; >Htc >change_vec_change_vec >change_vec_change_vec
+ >nth_change_vec // #Htb >Htb <(reverse_reverse ? ls0) in ⊢ (???%);
+ cases (reverse ? ls0)
+ [ %
+ | #l1 #ls1 >reverse_cons
+ >(?: list_of_tape ? (midtape ? (l0::reverse ? ls1@[l1]) c rs) =
+ l1::ls1@l0::c::rs)
+ [|change with (reverse ??@?) in ⊢ (??%?);
+ whd in match (left ??); >reverse_cons >reverse_append
+ whd in ⊢ (??%?); @eq_f >reverse_reverse normalize
+ >associative_append % ] % ]
+ ]
+]
+qed.