1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 include "turing/mono.ma".
19 - return its nth element
20 - return the index of a given element
22 axiom FS_crd : FinSet → nat.
23 axiom FS_nth : ∀F:FinSet.nat → option F.
24 axiom index_of_FS : ∀F:FinSet.F → nat.
26 (* unary bit representation (with a given length) of a certain number *)
27 axiom unary_of_nat : nat → nat → (list bool).
29 axiom FinVector : Type[0] → nat → FinSet.
31 definition binary_base_states ≝ initN 6.
33 definition bin0 : binary_base_states ≝ mk_Sig ?? 0 (leb_true_to_le 1 6 (refl …)).
34 definition bin1 : binary_base_states ≝ mk_Sig ?? 1 (leb_true_to_le 2 6 (refl …)).
35 definition bin2 : binary_base_states ≝ mk_Sig ?? 2 (leb_true_to_le 3 6 (refl …)).
36 definition bin3 : binary_base_states ≝ mk_Sig ?? 3 (leb_true_to_le 4 6 (refl …)).
37 definition bin4 : binary_base_states ≝ mk_Sig ?? 4 (leb_true_to_le 5 6 (refl …)).
38 definition bin5 : binary_base_states ≝ mk_Sig ?? 5 (leb_true_to_le 6 6 (refl …)).
40 definition states_binaryTM : FinSet → FinSet → FinSet ≝ λsig,states.
41 FinProd (FinProd states binary_base_states)
42 (FinProd (FinOption sig) (initN (S (S (2 * (FS_crd sig)))))).
44 axiom daemon : ∀T:Type[0].T.
46 definition to_initN : ∀n,m.n < m → initN m ≝ λn,m,Hn.mk_Sig … n ….// qed.
48 definition initN_pred : ∀n.∀m:initN n.initN n ≝ λn,m.mk_Sig … (pred (pi1 … m)) ….
49 cases m #m0 /2 by le_to_lt_to_lt/ qed.
51 definition displ_of_move ≝ λsig,mv.
57 lemma le_displ_of_move : ∀sig,mv.displ_of_move sig mv ≤ S (2*FS_crd sig).
61 (* controllare i contatori, molti andranno incrementati di uno *)
62 definition trans_binaryTM : ∀sig,states:FinSet.
63 (states × (option sig) → states × (option sig) × move) →
64 ((states_binaryTM sig states) × (option bool) →
65 (states_binaryTM sig states) × (option bool) × move)
66 ≝ λsig,states,trans,p.
68 let 〈s0,phase,ch,count〉 ≝ s in
69 let (H1 : O < S (S (2*FS_crd sig))) ≝ ? in
70 let (H2 : FS_crd sig < S (S (2*FS_crd sig))) ≝ ? in
71 match pi1 … phase with
72 [ O ⇒ (*** PHASE 0: read ***)
73 match pi1 … count with
74 [ O ⇒ 〈〈s0,bin1,ch,to_initN (FS_crd sig) ? H2〉,None ?,N〉
76 [ Some a0 ⇒ if (a0 == true)
77 then 〈〈s0,bin0,FS_nth sig k,initN_pred … count〉, None ?,R〉
78 else 〈〈s0,bin0,ch,initN_pred … count〉,None ?,R〉
79 | None ⇒ (* Overflow position! *)
80 let 〈s',a',mv〉 ≝ trans 〈s0,None ?〉 in
82 [ None ⇒ (* we don't write anything: go to end of 2 *) 〈〈s0,bin2,None ?,to_initN 0 ? H1〉,None ?,N〉
83 | Some _ ⇒ (* maybe extend tape *) 〈〈s0,bin4,None ?,to_initN O ? H1〉,None ?,R〉 ] ] ]
84 | S phase ⇒ match phase with
85 [ O ⇒ (*** PHASE 1: restart ***)
86 match pi1 … count with
87 [ O ⇒ 〈〈s0,bin2,ch,to_initN (FS_crd sig) ? H2〉,None ?,N〉
88 | S k ⇒ 〈〈s0,bin1,ch,initN_pred … count〉,None ?,L〉 ]
89 | S phase ⇒ match phase with
90 [ O ⇒ (*** PHASE 2: write ***)
91 let 〈s',a',mv〉 ≝ trans 〈s0,ch〉 in
92 match pi1 … count with
93 [ O ⇒ 〈〈s',bin3,ch,to_initN (displ_of_move sig mv) ??〉,None ?,N〉
95 [ None ⇒ 〈〈s0,bin2,ch,initN_pred … count〉,None ?,R〉
96 | Some a0' ⇒ let out ≝ (FS_nth ? k == a') in
97 〈〈s0,bin2,ch,initN_pred … count〉,Some ? out,R〉 ]
99 | S phase ⇒ match phase with
100 [ O ⇒ (*** PHASE 3: move head left ***)
101 match pi1 … count with
102 [ O ⇒ 〈〈s0,bin0,None ?,to_initN (FS_crd sig) ? H2〉, None ?,N〉 (* the end: restart *)
103 | S k ⇒ 〈〈s0,bin3,ch,initN_pred … count〉, None ?,L〉 ]
104 | S phase ⇒ match phase with
105 [ O ⇒ (*** PHASE 4: check position ***)
107 [ None ⇒ (* niltape/rightof: we can write *) 〈〈s0,bin2,ch,to_initN (FS_crd sig) ? H2〉,None ?,N〉
108 | Some _ ⇒ (* leftof *)
109 let 〈s',a',mv〉 ≝ trans 〈s0,ch〉 in
111 [ None ⇒ (* (vacuous) go to end of 2 *) 〈〈s0,bin2,ch,to_initN 0 ? H1〉,None ?,N〉
112 | Some _ ⇒ (* extend tape *) 〈〈s0,bin5,ch,to_initN (FS_crd sig) ? H2〉,None ?,L〉 ]
114 | S _ ⇒ (*** PHASE 5: left extension ***)
115 match pi1 … count with
116 [ O ⇒ 〈〈s0,bin2,ch,to_initN (FS_crd sig) ? H2〉,None ?,R〉
117 | S k ⇒ 〈〈s0,bin5,ch,initN_pred … count〉,Some ? false,L〉 ]]]]]].
118 [2,3: /2 by lt_S_to_lt/] /2 by le_S_S/
121 definition halt_binaryTM : ∀sig,M.states_binaryTM sig (states sig M) → bool ≝
122 λsig,M,s.let 〈s0,phase,ch,count〉 ≝ s in
123 pi1 … phase == O ∧ halt sig M s0.
126 * Una mk_binaryTM prende in input una macchina M e produce una macchina che:
127 * - ha per alfabeto FinBool
128 * - ha stati di tipo ((states … M) × (initN 7)) ×
129 ((option sig) × (initN (2*dimensione dell'alfabeto di M + 1))
130 * dove il primo elemento corrisponde allo stato della macchina input,
131 * il secondo identifica la fase (lettura, scrittura, spostamento)
132 * il terzo identifica il carattere oggetto letto
133 * il quarto è un contatore
134 * - la funzione di transizione viene prodotta da trans_binaryTM
135 * - la funzione di arresto viene prodotta da halt_binaryTM
137 definition mk_binaryTM ≝
139 mk_TM FinBool (states_binaryTM sig (states sig M))
140 (trans_binaryTM sig (states sig M) (trans sig M))
141 (〈start sig M,bin0,None ?,FS_crd sig〉) (halt_binaryTM sig M).
142 /2 by lt_S_to_lt/ qed.
144 definition bin_char ≝ λsig,ch.unary_of_nat (FS_crd sig) (index_of_FS sig ch).
146 definition opt_bin_char ≝ λsig,c.match c with
147 [ None ⇒ [ ] | Some c0 ⇒ bin_char sig c0 ].
149 definition bin_list ≝ λsig,l.flatten ? (map ?? (bin_char sig) l).
150 definition rev_bin_list ≝ λsig,l.flatten ? (map ?? (λc.reverse ? (bin_char sig c)) l).
152 definition tape_bin_lift ≝ λsig,t.
153 let ls' ≝ rev_bin_list ? (left ? t) in
154 let c' ≝ option_hd ? (opt_bin_char sig (current ? t)) in
155 let rs' ≝ (tail ? (opt_bin_char sig (current ? t))@bin_list ? (right ? t)) in
156 mk_tape ? ls' c' rs'.
158 definition R_bin_lift ≝ λsig,R,t1,t2.
159 ∃u1.t1 = tape_bin_lift sig u1 →
160 ∃u2.t2 = tape_bin_lift sig u2 ∧ R u1 u2.
162 definition state_bin_lift :
163 ∀sig.∀M:TM sig.states sig M → states ? (mk_binaryTM ? M)
164 ≝ λsig,M,q.〈q,bin0,None ?,FS_crd sig〉./2 by lt_S_to_lt/ qed.
166 lemma lift_halt_binaryTM :
167 ∀sig,M,q.halt sig M q = halt ? (mk_binaryTM sig M) (state_bin_lift ? M q).
170 lemma binaryTM_bin0_bin1 :
172 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin0,ch,O〉) t)
173 = mk_config ?? (〈q,bin1,ch,to_initN (FS_crd sig) ??〉) t. //
176 lemma binaryTM_bin0_bin2 :
177 ∀sig,M,t,q,ch,k,qn,mv.
178 current ? t = None ? → S k <S (2*FS_crd sig) →
179 〈qn,None ?,mv〉 = trans sig M 〈q,None ?〉 →
180 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin0,ch,S k〉) t)
181 = mk_config ?? (〈q,bin2,None ?,to_initN O ??〉) t. [2,3:/2 by transitive_lt/]
182 #sig #M #t #q #ch #k #qn #mv #Hcur #Hk #Htrans
183 whd in match (step ???); whd in match (trans ???);
187 lemma binaryTM_bin0_bin4 :
188 ∀sig,M,t,q,ch,k,qn,chn,mv.
189 current ? t = None ? → S k <S (2*FS_crd sig) →
190 〈qn,Some ? chn,mv〉 = trans sig M 〈q,None ?〉 →
191 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin0,ch,S k〉) t)
192 = mk_config ?? (〈q,bin4,None ?,to_initN 0 ??〉) (tape_move ? t R). [2,3:/2 by transitive_lt/]
193 #sig #M #t #q #ch #k #qn #chn #mv #Hcur #Hk #Htrans
194 whd in match (step ???); whd in match (trans ???);
198 lemma binaryTM_bin0_true :
200 current ? t = Some ? true → S k <S (2*FS_crd sig) →
201 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin0,ch,S k〉) t)
202 = mk_config ?? (〈q,bin0,FS_nth sig k,to_initN k ??〉) (tape_move ? t R).[2,3:@le_S /2 by lt_S_to_lt/]
203 #sig #M #t #q #ch #k #Hcur #Hk
204 whd in match (step ???); whd in match (trans ???);
208 lemma binaryTM_bin0_false :
210 current ? t = Some ? false → S k <S (2*FS_crd sig) →
211 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin0,ch,S k〉) t)
212 = mk_config ?? (〈q,bin0,ch,to_initN k ??〉) (tape_move ? t R).[2,3:@le_S /2 by lt_S_to_lt/]
213 #sig #M #t #q #ch #k #Hcur #Hk
214 whd in match (step ???); whd in match (trans ???);
219 axiom binary_to_bin_char :∀sig,csl,csr,a.
220 csl@true::csr=bin_char sig a → FS_nth ? (length ? csr) = Some ? a.
222 lemma binaryTM_phase0_midtape_aux :
225 ∀csr,csl,t,ch.length ? csr < S (2*FS_crd sig) →
226 t = mk_tape ? (reverse ? csl@ls) (option_hd ? (csr@rs)) (tail ? (csr@rs)) →
227 csl@csr = bin_char sig a →
228 |csl@csr| = FS_crd sig →
229 (index_of_FS ? a < |csl| → ch = Some ? a) →
230 loopM ? (mk_binaryTM sig M) (S (length ? csr) + k)
231 (mk_config ?? (〈q,bin0,ch,length ? csr〉) t)
232 = loopM ? (mk_binaryTM sig M) k
233 (mk_config ?? (〈q,bin1,Some ? a,FS_crd sig〉)
234 (mk_tape ? (reverse ? (bin_char ? a)@ls) (option_hd ? rs) (tail ? rs))). [2,3:@le_S /2 by O/]
235 #sig #M #q #ls #a #rs #k #Hhalt #csr elim csr
236 [ #csl #t #ch #Hlen #Ht >append_nil #Hcsl #Hlencsl #Hch >loopM_unfold >loop_S_false [|normalize //]
237 >Hch [| >Hlencsl (* lemmatize *) @daemon]
238 <loopM_unfold @eq_f >binaryTM_bin0_bin1 @eq_f >Ht
239 whd in match (step ???); whd in match (trans ???); <Hcsl %
241 [ #csr0 #IH #csl #t #ch #Hlen #Ht #Heq #Hcrd #Hch >loopM_unfold >loop_S_false [|normalize //]
242 <loopM_unfold lapply (binary_to_bin_char … Heq) #Ha >binaryTM_bin0_true
244 lapply (IH (csl@[true]) (tape_move FinBool t R) ??????)
246 | >associative_append @Hcrd
247 | >associative_append @Heq
248 | >Ht whd in match (option_hd ??) in ⊢ (??%?); whd in match (tail ??) in ⊢ (??%?);
251 [ normalize >rev_append_def >rev_append_def >reverse_append %
252 | #r1 #rs1 normalize >rev_append_def >rev_append_def >reverse_append % ]
253 | #c1 #csr1 normalize >rev_append_def >rev_append_def >reverse_append % ]
256 #H whd in match (plus ??); >H @eq_f @eq_f2 %
257 | #csr0 #IH #csl #t #ch #Hlen #Ht #Heq #Hcrd #Hch >loopM_unfold >loop_S_false [|normalize //]
258 <loopM_unfold >binaryTM_bin0_false [| >Ht % ]
259 lapply (IH (csl@[false]) (tape_move FinBool t R) ??????)
261 | (* by cases: if index < |csl|, then Hch, else False *)
263 | >associative_append @Hcrd
264 | >associative_append @Heq
265 | >Ht whd in match (option_hd ??) in ⊢ (??%?); whd in match (tail ??) in ⊢ (??%?);
268 [ normalize >rev_append_def >rev_append_def >reverse_append %
269 | #r1 #rs1 normalize >rev_append_def >rev_append_def >reverse_append % ]
270 | #c1 #csr1 normalize >rev_append_def >rev_append_def >reverse_append % ]
273 #H whd in match (plus ??); >H @eq_f @eq_f2 %
278 lemma le_to_eq : ∀m,n.m ≤ n → ∃k. n = m + k. /3 by plus_minus, ex_intro/
281 lemma minus_tech : ∀a,b.a + b - a = b. // qed.
283 lemma binaryTM_phase0_midtape :
284 ∀sig,M,t,q,ls,a,rs,ch,k.
285 halt sig M q=false → S (FS_crd sig) ≤ k →
286 t = mk_tape ? ls (option_hd ? (bin_char ? a)) (tail ? (bin_char sig a)@rs) →
287 loopM ? (mk_binaryTM sig M) k
288 (mk_config ?? (〈q,bin0,ch,FS_crd sig〉) t)
289 = loopM ? (mk_binaryTM sig M) (k - S (FS_crd sig))
290 (mk_config ?? (〈q,bin1,Some ? a,FS_crd sig〉)
291 (mk_tape ? (reverse ? (bin_char ? a)@ls) (option_hd ? rs) (tail ? rs))). [|*:@le_S //]
292 #sig #M #t #q #ls #a #rs #ch #k #Hhalt #Hk #Ht
293 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
294 cut (∃c,cl.bin_char sig a = c::cl) [@daemon] * #c * #cl #Ha >Ha
295 cut (FS_crd sig = |bin_char sig a|) [@daemon] #Hlen
296 @(trans_eq ?? (loopM ? (mk_binaryTM ? M) (S (|c::cl|) + k0)
297 (mk_config ?? 〈q,bin0,〈ch,|c::cl|〉〉 t)))
298 [ /2 by O/ | @eq_f2 // @eq_f2 // @eq_f <Ha >Hlen % ]
299 >(binaryTM_phase0_midtape_aux ? M q ls a rs ? ? (c::cl) [ ] t ch) //
300 [| normalize #Hfalse @False_ind cases (not_le_Sn_O ?) /2/
301 | <Ha (* |bin_char sig ?| = FS_crd sig *) @daemon
308 lemma binaryTM_phase0_None_None :
309 ∀sig,M,t,q,ch,k,n,qn,mv.
310 O < n → n < 2*FS_crd sig → O < k →
312 current ? t = None ? →
313 〈qn,None ?,mv〉 = trans sig M 〈q,None ?〉 →
314 loopM ? (mk_binaryTM sig M) k (mk_config ?? (〈q,bin0,ch,n〉) t)
315 = loopM ? (mk_binaryTM sig M) (k-1)
316 (mk_config ?? (〈q,bin2,None ?,to_initN O ??〉) t). [2,3: /2 by transitive_lt/ ]
317 #sig #M #t #q #ch #k #n #qn #mv #HOn #Hn #Hk #Hhalt
318 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
319 cases (le_to_eq … HOn) #n0 #Hn0 destruct (Hn0)
321 [ >loopM_unfold >loop_S_false [|@Hhalt] #Hcur #Htrans >binaryTM_bin0_bin2 // /2 by refl, transitive_lt/
322 | #r0 #rs0 >loopM_unfold >loop_S_false [|@Hhalt] #Hcur #Htrans >binaryTM_bin0_bin2 // /2 by refl, transitive_lt/
323 | #l0 #ls0 >loopM_unfold >loop_S_false [|@Hhalt] #Hcur #Htrans >binaryTM_bin0_bin2 // /2 by refl, transitive_lt/
324 | #ls #cur #rs normalize in ⊢ (%→?); #H destruct (H) ]
327 lemma binaryTM_phase0_None_Some :
328 ∀sig,M,t,q,ch,k,n,qn,chn,mv.
329 O < n → n < 2*FS_crd sig → O < k →
331 current ? t = None ? →
332 〈qn,Some ? chn,mv〉 = trans sig M 〈q,None ?〉 →
333 loopM ? (mk_binaryTM sig M) k (mk_config ?? (〈q,bin0,ch,n〉) t)
334 = loopM ? (mk_binaryTM sig M) (k-1)
335 (mk_config ?? (〈q,bin4,None ?,to_initN O ??〉) (tape_move ? t R)). [2,3: /2 by transitive_lt/ ]
336 #sig #M #t #q #ch #k #n #qn #chn #mv #HOn #Hn #Hk #Hhalt
337 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
338 cases (le_to_eq … HOn) #n0 #Hn0 destruct (Hn0)
340 [ >loopM_unfold >loop_S_false [|@Hhalt] #Hcur #Htrans >binaryTM_bin0_bin4 // /2 by refl, transitive_lt/
341 | #r0 #rs0 >loopM_unfold >loop_S_false [|@Hhalt] #Hcur #Htrans >binaryTM_bin0_bin4 // /2 by refl, transitive_lt/
342 | #l0 #ls0 >loopM_unfold >loop_S_false [|@Hhalt] #Hcur #Htrans >binaryTM_bin0_bin4 // /2 by refl, transitive_lt/
343 | #ls #cur #rs normalize in ⊢ (%→?); #H destruct (H) ]
346 lemma binaryTM_bin1_O :
348 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin1,ch,O〉) t)
349 = mk_config ?? (〈q,bin2,ch,to_initN (FS_crd sig) ??〉) t. [2,3:/2 by lt_S_to_lt/]
353 lemma binaryTM_bin1_S :
354 ∀sig,M,t,q,ch,k. S k <S (2*FS_crd sig) →
355 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin1,ch,S k〉) t)
356 = mk_config ?? (〈q,bin1,ch,to_initN k ??〉) (tape_move ? t L). [2,3:@le_S /2 by lt_S_to_lt/]
357 #sig #M #t #q #ch #k #HSk %
360 lemma binaryTM_phase1 :
361 ∀sig,M,q,ls1,ls2,cur,rs,ch,k.
362 S (FS_crd sig) ≤ k → |ls1| = FS_crd sig → (cur = None ? → rs = [ ]) →
363 loopM ? (mk_binaryTM sig M) k
364 (mk_config ?? (〈q,bin1,ch,FS_crd sig〉) (mk_tape ? (ls1@ls2) cur rs))
365 = loopM ? (mk_binaryTM sig M) (k - S (FS_crd sig))
366 (mk_config ?? (〈q,bin2,ch,FS_crd sig〉)
367 (mk_tape ? ls2 (option_hd ? (reverse ? ls1@option_cons ? cur rs))
368 (tail ? (reverse ? ls1@option_cons ? cur rs)))). [2,3:/2 by O/]
369 cut (∀sig,M,q,ls1,ls2,ch,k,n,cur,rs.
370 |ls1| = n → n<S (2*FS_crd sig) → (cur = None ? → rs = [ ]) →
371 loopM ? (mk_binaryTM sig M) (S n + k)
372 (mk_config ?? (〈q,bin1,ch,n〉) (mk_tape ? (ls1@ls2) cur rs))
373 = loopM ? (mk_binaryTM sig M) k
374 (mk_config ?? (〈q,bin2,ch,FS_crd sig〉)
375 (mk_tape ? ls2 (option_hd ? (reverse ? ls1@option_cons ? cur rs))
376 (tail ? (reverse ? ls1@option_cons ? cur rs))))) [1,2:@le_S //]
377 [ #sig #M #q #ls1 #ls2 #ch #k elim ls1
378 [ #n normalize in ⊢ (%→?); #cur #rs #Hn <Hn #Hcrd #Hcur >loopM_unfold >loop_S_false [| % ]
379 >binaryTM_bin1_O cases cur in Hcur;
380 [ #H >(H (refl ??)) -H %
382 | #l0 #ls0 #IH * [ #cur #rs normalize in ⊢ (%→?); #H destruct (H) ]
383 #n #cur #rs normalize in ⊢ (%→?); #H destruct (H) #Hlt #Hcur
384 >loopM_unfold >loop_S_false [|%] >binaryTM_bin1_S
385 <(?:mk_tape ? (ls0@ls2) (Some ? l0) (option_cons ? cur rs) =
386 tape_move FinBool (mk_tape FinBool ((l0::ls0)@ls2) cur rs) L)
387 [| cases cur in Hcur; [ #H >(H ?) // | #cur' #_ % ] ]
388 >(?:loop (config FinBool (states FinBool (mk_binaryTM sig M))) (S (|ls0|)+k)
389 (step FinBool (mk_binaryTM sig M))
390 (λc:config FinBool (states FinBool (mk_binaryTM sig M))
391 .halt FinBool (mk_binaryTM sig M)
392 (cstate FinBool (states FinBool (mk_binaryTM sig M)) c))
393 (mk_config FinBool (states FinBool (mk_binaryTM sig M))
394 〈q,bin1,ch,to_initN (|ls0|) ?
395 (le_S ?? (lt_S_to_lt (|ls0|) (S (2*FS_crd sig)) Hlt))〉
396 (mk_tape FinBool (ls0@ls2) (Some FinBool l0) (option_cons FinBool cur rs)))
397 = loopM FinBool (mk_binaryTM sig M) k
398 (mk_config FinBool (states FinBool (mk_binaryTM sig M))
399 〈q,bin2,〈ch,FS_crd sig〉〉
401 (option_hd FinBool (reverse FinBool ls0@l0::option_cons FinBool cur rs))
402 (tail FinBool (reverse FinBool ls0@l0::option_cons FinBool cur rs)))))
404 | >(?: l0::option_cons ? cur rs = option_cons ? (Some ? l0) (option_cons ? cur rs)) [| % ]
405 @trans_eq [|| @(IH ??? (refl ??)) [ /2 by lt_S_to_lt/ | #H destruct (H) ] ]
408 >reverse_cons >associative_append %
410 | #Hcut #sig #M #q #ls1 #ls2 #cur #rs #ch #k #Hk #Hlen
411 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech @Hcut // ]
414 lemma binaryTM_bin2_O :
415 ∀sig,M,t,q,qn,ch,chn,mv.
416 〈qn,chn,mv〉 = trans sig M 〈q,ch〉 →
417 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin2,ch,O〉) t)
418 = mk_config ?? (〈qn,bin3,ch,to_initN (displ_of_move sig mv) ??〉) t.[2,3:/2 by lt_S_to_lt,le_S_S/]
419 #sig #M #t #q #qn #ch #chn #mv #Htrans
420 whd in match (step ???); whd in match (trans ???); <Htrans %
423 lemma binaryTM_bin2_S_None :
424 ∀sig,M,t,q,qn,ch,mv,k.
425 k < S (2*FS_crd sig) →
426 〈qn,None ?,mv〉 = trans sig M 〈q,ch〉 →
427 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin2,ch,S k〉) t)
428 = mk_config ?? (〈q,bin2,ch,k〉) (tape_move ? t R).
429 [2,3: @le_S_S /2 by lt_to_le/ ]
430 #sig #M #t #q #qn #ch #mv #k #Hk #Htrans
431 whd in match (step ???); whd in match (trans ???); <Htrans %
434 lemma binaryTM_bin2_S_Some :
435 ∀sig,M,t,q,qn,ch,chn,mv,k.
436 k< S (2*FS_crd sig) →
437 〈qn,Some ? chn,mv〉 = trans sig M 〈q,ch〉 →
438 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin2,ch,S k〉) t)
439 = mk_config ?? (〈q,bin2,ch,k〉) (tape_move ? (tape_write ? t (Some ? (FS_nth ? k == Some ? chn))) R).
440 [2,3: @le_S_S /2 by lt_to_le/ ]
441 #sig #M #t #q #qn #ch #chn #mv #k #Hk #Htrans
442 whd in match (step ???); whd in match (trans ???); <Htrans %
445 let rec iter (T:Type[0]) f n (t:T) on n ≝
446 match n with [ O ⇒ t | S n0 ⇒ iter T f n0 (f t) ].
448 lemma binaryTM_phase2_None :∀sig,M,q,ch,qn,mv,k,n. S n ≤ k →
449 ∀t.n≤S (2*FS_crd sig) →
450 〈qn,None ?,mv〉 = trans sig M 〈q,ch〉 →
451 loopM ? (mk_binaryTM sig M) k
452 (mk_config ?? (〈q,bin2,ch,n〉) t)
453 = loopM ? (mk_binaryTM sig M) (k - S n)
454 (mk_config ?? (〈qn,bin3,ch,to_initN (displ_of_move sig mv) ??〉)
455 (iter ? (λt0.tape_move ? t0 R) n t)). [2,3: @le_S_S /2 by lt_S_to_lt/]
456 #sig #M #q #ch #qn #mv #k #n #Hk
457 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
459 [ #t #Hle #Htrans >loopM_unfold >loop_S_false //
460 >(binaryTM_bin2_O … Htrans) //
461 | #n0 #IH #t #Hn0 #Htrans >loopM_unfold >loop_S_false //
462 >(binaryTM_bin2_S_None … Htrans) @(trans_eq ???? (IH …)) //
466 lemma binaryTM_phase2_Some_of : ∀sig,M,q,ch,qn,chn,mv,ls,k.
467 S (FS_crd sig) ≤ k → 〈qn,Some ? chn,mv〉 = trans sig M 〈q,ch〉 →
468 loopM ? (mk_binaryTM sig M) k
469 (mk_config ?? (〈q,bin2,ch,FS_crd sig〉) (mk_tape ? ls (None ?) [ ]))
470 = loopM ? (mk_binaryTM sig M) (k - S (FS_crd sig))
471 (mk_config ?? (〈qn,bin3,ch,displ_of_move sig mv〉)
472 (mk_tape ? (reverse ? (bin_char sig chn)@ls) (None ?) [ ])). [2,3:@le_S_S //]
473 cut (∀sig,M,q,ch,qn,chn,mv,ls,k,n.
474 S n ≤ k → 〈qn,Some ? chn,mv〉 = trans sig M 〈q,ch〉 →
475 ∀csl. n <S (2*FS_crd sig) →
476 |csl| + n = FS_crd sig →
477 (∃fs.bin_char sig chn = reverse ? csl@fs) →
478 loopM ? (mk_binaryTM sig M) k
479 (mk_config ?? (〈q,bin2,ch,n〉) (mk_tape ? (csl@ls) (None ?) [ ]))
480 = loopM ? (mk_binaryTM sig M) (k - S n)
481 (mk_config ?? (〈qn,bin3,ch,displ_of_move sig mv〉)
482 (mk_tape ? (reverse ? (bin_char sig chn)@ls) (None ?) [ ]))) [1,2:@le_S_S //]
483 [ #sig #M #q #ch #qn #chn #mv #ls #k #n #Hk
484 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
486 [ #csl #Hcount #Hcrd * #fs #Hfs >loopM_unfold >loop_S_false // <loopM_unfold
488 [ cases fs in Hfs; // #f0 #fs0 #H lapply (eq_f ?? (length ?) … H)
489 >length_append >(?:|bin_char sig chn| = FS_crd sig) [|@daemon]
490 <Hcrd >length_reverse #H1 cut (O = |f0::fs0|) [ /2/ ]
491 normalize #H1 destruct (H1) ]
492 #H destruct (H) >append_nil in Hfs; #Hfs
493 >Hfs >reverse_reverse >(binaryTM_bin2_O … Htrans) //
494 | #n0 #IH #csl #Hcount #Hcrd * #fs #Hfs
495 >loopM_unfold >loop_S_false // <loopM_unfold
496 >(?: step FinBool (mk_binaryTM sig M)
497 (mk_config FinBool (states FinBool (mk_binaryTM sig M)) 〈q,bin2,〈ch,S n0〉〉
498 (mk_tape FinBool (csl@ls) (None FinBool) []))
499 = mk_config ?? (〈q,bin2,ch,n0〉)
500 (tape_move ? (tape_write ?
501 (mk_tape ? (csl@ls) (None ?) [ ]) (Some ? (FS_nth ? n0 == Some ? chn))) R))
502 [| /2 by lt_S_to_lt/ | @(binaryTM_bin2_S_Some … Htrans) ]
503 >(?: tape_move ? (tape_write ???) ? =
504 mk_tape ? (((FS_nth ? n0 == Some sig chn)::csl)@ls) (None ?) [ ])
505 [| cases csl // cases ls // ]
507 [ #Hfalse cut (|bin_char ? chn| = |csl|) [ >Hfalse >length_append >length_reverse // ]
508 -Hfalse >(?:|bin_char sig chn| = FS_crd sig) [|@daemon]
509 <Hcrd in ⊢ (%→?); >(?:|csl| = |csl|+ O) in ⊢ (???%→?); //
510 #Hfalse cut (S n0 = O) /2 by injective_plus_r/ #H destruct (H)
512 cut (bin_char ? chn = reverse ? csl@(FS_nth ? n0 == Some ? chn)::fs0) [@daemon]
513 -Hbinchar #Hbinchar >Hbinchar @(trans_eq ???? (IH …)) //
514 [ %{fs0} >reverse_cons >associative_append @Hbinchar
515 | whd in ⊢ (??%?); /2 by / ]
516 @eq_f @eq_f @eq_f3 //
519 | #Hcut #sig #M #q #ch #qn #chn #mv #ls #k #Hk #Htrans
521 [3: @(trans_eq ???? (Hcut ??????? ls ? (FS_crd sig) ? Htrans …)) //
522 [3:@([ ]) | %{(bin_char ? chn)} % | % ]
527 lemma binaryTM_phase2_Some_ow : ∀sig,M,q,ch,qn,chn,mv,ls,k,cs,rs.
528 S (FS_crd sig) ≤ k → 〈qn,Some ? chn,mv〉 = trans sig M 〈q,ch〉 →
530 loopM ? (mk_binaryTM sig M) k
531 (mk_config ?? (〈q,bin2,ch,FS_crd sig〉)
532 (mk_tape ? ls (option_hd ? (cs@rs)) (tail ? (cs@rs))))
533 = loopM ? (mk_binaryTM sig M) (k - S (FS_crd sig))
534 (mk_config ?? (〈qn,bin3,ch,displ_of_move sig mv〉)
535 (mk_tape ? (reverse ? (bin_char sig chn)@ls) (option_hd ? rs) (tail ? rs))). [2,3:@le_S_S /2 by O/]
536 cut (∀sig,M,q,ch,qn,chn,mv,ls,rs,k,csr.
537 〈qn,Some ? chn,mv〉 = trans sig M 〈q,ch〉 →
538 ∀csl.|csr|<S (2*FS_crd sig) →
539 |csl@csr| = FS_crd sig →
540 (∃fs.bin_char sig chn = reverse ? csl@fs) →
541 loopM ? (mk_binaryTM sig M) (S (|csr|) + k)
542 (mk_config ?? (〈q,bin2,ch,|csr|〉)
543 (mk_tape ? (csl@ls) (option_hd ? (csr@rs)) (tail ? (csr@rs))))
544 = loopM ? (mk_binaryTM sig M) k
545 (mk_config ?? (〈qn,bin3,ch,displ_of_move sig mv〉)
546 (mk_tape ? (reverse ? (bin_char sig chn)@ls) (option_hd ? rs) (tail ? rs)))) [1,2: @le_S_S /2 by le_S/]
547 [ #sig #M #q #ch #qn #chn #mv #ls #rs #k #csr #Htrans elim csr
548 [ #csl #Hcount #Hcrd * #fs #Hfs >loopM_unfold >loop_S_false // normalize in match (length ? [ ]);
549 >(binaryTM_bin2_O … Htrans) <loopM_unfold @eq_f @eq_f @eq_f3 //
550 cases fs in Hfs; // #f0 #fs0 #H lapply (eq_f ?? (length ?) … H)
551 >length_append >(?:|bin_char sig chn| = FS_crd sig) [|@daemon]
552 <Hcrd >length_reverse #H1 cut (O = |f0::fs0|) [ /2/ ]
553 normalize #H1 destruct (H1)
554 | #b0 #bs0 #IH #csl #Hcount #Hcrd * #fs #Hfs
555 >loopM_unfold >loop_S_false // >(binaryTM_bin2_S_Some … Htrans)
556 >(?: tape_move ? (tape_write ???) ? =
557 mk_tape ? (((FS_nth ? (|bs0|)==Some sig chn)::csl)@ls)
558 (option_hd ? (bs0@rs)) (tail ? (bs0@rs)))
559 in match (tape_move ? (tape_write ???) ?);
560 [| cases bs0 // cases rs // ] @IH
561 [ whd in Hcount:(?%?); /2 by lt_S_to_lt/
562 | <Hcrd >length_append >length_append normalize //
564 [ #Hfalse cut (|bin_char ? chn| = |csl|) [ >Hfalse >length_append >length_reverse // ] -Hfalse >(?:|bin_char sig chn| = FS_crd sig) [|@daemon]
565 <Hcrd >length_append normalize >(?:|csl| = |csl|+ O) in ⊢ (???%→?); //
566 #Hfalse cut (S (|bs0|) = O) /2 by injective_plus_r/ #H destruct (H)
568 cut (bin_char ? chn = reverse ? csl@(FS_nth ? (|bs0|) == Some ? chn)::fs0) [@daemon]
569 -Hbinchar #Hbinchar >Hbinchar %{fs0} >reverse_cons >associative_append %
573 | #Hcut #sig #M #q #ch #qn #chn #mv #ls #k #cs #rs #Hk #Htrans #Hcrd
574 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech @trans_eq
575 [3: @(trans_eq ???? (Hcut ??????? ls ?? cs Htrans [ ] …)) //
576 [ normalize % // | normalize @Hcrd | >Hcrd // ]
577 || @eq_f2 [ >Hcrd % | @eq_f2 // @eq_f cases Hcrd // ] ] ]
580 lemma binaryTM_bin3_O :
582 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin3,ch,O〉) t)
583 = mk_config ?? (〈q,bin0,None ?,to_initN (FS_crd sig) ??〉) t. [2,3:@le_S //]
587 lemma binaryTM_bin3_S :
588 ∀sig,M,t,q,ch,k. S k ≤ S (2*FS_crd sig) →
589 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin3,ch,S k〉) t)
590 = mk_config ?? (〈q,bin3,ch,to_initN k ??〉) (tape_move ? t L). [2,3: @le_S_S /2 by lt_to_le/]
591 #sig #M #t #q #ch #k #HSk %
594 lemma binaryTM_phase3 :∀sig,M,q,ch,k,n.
595 S n ≤ k → n ≤ S (2*FS_crd sig) →
596 ∀t.loopM ? (mk_binaryTM sig M) k
597 (mk_config ?? (〈q,bin3,ch,n〉) t)
598 = loopM ? (mk_binaryTM sig M) (k - S n)
599 (mk_config ?? (〈q,bin0,None ?,FS_crd sig〉)
600 (iter ? (λt0.tape_move ? t0 L) n t)). [2,3: /2 by lt_S_to_lt, le_to_lt_to_lt/]
601 #sig #M #q #ch #k #n #Hk
602 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech elim n
603 [ #Hcrd #t >loopM_unfold >loop_S_false [| % ] >binaryTM_bin3_O //
604 | #n0 #IH #Hlt #t >loopM_unfold >loop_S_false [|%] >binaryTM_bin3_S [|//]
605 <IH [|/2 by lt_to_le/]
609 lemma binaryTM_bin4_None :
611 current ? t = None ? →
612 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin4,ch,O〉) t)
613 = mk_config ?? (〈q,bin2,ch,to_initN (FS_crd sig) ??〉) t. [2,3: @le_S //]
614 #sig #M #t #q #ch #Hcur whd in ⊢ (??%?); >Hcur %
617 lemma binaryTM_phase4_write : ∀sig,M,q,ch,k,t.
618 O < k → current ? t = None ? →
619 loopM ? (mk_binaryTM sig M) k
620 (mk_config ?? (〈q,bin4,ch,O〉) t)
621 = loopM ? (mk_binaryTM sig M) (k-1)
622 (mk_config ?? (〈q,bin2,ch,to_initN (FS_crd sig) ??〉) t). [2,3: @le_S //]
623 #sig #M #q #ch #k #t #Hk #Hcur
624 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
625 >loopM_unfold >loop_S_false // <loopM_unfold >binaryTM_bin4_None //
628 (* we don't get here any more! *
629 lemma binaryTM_bin4_noextend :
630 ∀sig,M,t,q,ch,cur,qn,mv.
631 current ? t = Some ? cur →
632 〈qn,None ?,mv〉 = trans sig M 〈q,ch〉 →
633 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin4,ch,O〉) t)
634 = mk_config ?? (〈q,bin2,ch,to_initN O ??〉) t. [2,3://]
635 #sig #M #t #q #ch #cur #qn #mv #Hcur #Htrans
636 whd in ⊢ (??%?); >Hcur whd in ⊢ (??%?);
637 whd in match (trans FinBool ??); <Htrans %
641 lemma binaryTM_bin4_extend :
642 ∀sig,M,t,q,ch,cur,qn,an,mv.
643 current ? t = Some ? cur →
644 〈qn,Some ? an,mv〉 = trans sig M 〈q,ch〉 →
645 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin4,ch,O〉) t)
646 = mk_config ?? (〈q,bin5,ch,to_initN (FS_crd sig) ??〉) (tape_move ? t L). [2,3:@le_S //]
647 #sig #M #t #q #ch #cur #qn #an #mv #Hcur #Htrans
648 whd in ⊢ (??%?); >Hcur whd in ⊢ (??%?);
649 whd in match (trans FinBool ??); <Htrans %
652 lemma binaryTM_phase4_extend : ∀sig,M,q,ch,k,t,cur,qn,an,mv.
653 O < k → current ? t = Some ? cur →
654 〈qn,Some ? an,mv〉 = trans sig M 〈q,ch〉 →
655 loopM ? (mk_binaryTM sig M) k
656 (mk_config ?? (〈q,bin4,ch,O〉) t)
657 = loopM ? (mk_binaryTM sig M) (k-1)
658 (mk_config ?? (〈q,bin5,ch,to_initN (FS_crd sig) ??〉) (tape_move ? t L)). [2,3: @le_S //]
659 #sig #M #q #ch #k #t #cur #qn #an #mv #Hk #Hcur #Htrans
660 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
661 >loopM_unfold >loop_S_false // <loopM_unfold >binaryTM_bin4_extend //
664 lemma binaryTM_bin5_O :
666 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin5,ch,O〉) t)
667 = mk_config ?? (〈q,bin2,ch,to_initN (FS_crd sig) ??〉) (tape_move ? t R). [2,3:@le_S //]
671 lemma binaryTM_bin5_S :
672 ∀sig,M,t,q,ch,k. S k <S (2*FS_crd sig) →
673 step ? (mk_binaryTM sig M) (mk_config ?? (〈q,bin5,ch,S k〉) t)
674 = mk_config ?? (〈q,bin5,ch,to_initN k ??〉) (tape_move ? (tape_write ? t (Some ? false)) L). [2,3:@le_S /2 by lt_S_to_lt/]
675 #sig #M #t #q #ch #k #HSk %
678 (* extends the tape towards the left with an unimportant sequence that will be
679 immediately overwritten *)
680 lemma binaryTM_phase5 :∀sig,M,q,ch,k,n. S n ≤ k →
681 ∀rs.n<S (2*FS_crd sig) →
683 loopM ? (mk_binaryTM sig M) k
684 (mk_config ?? (〈q,bin5,ch,n〉) (mk_tape ? [] (None ?) rs))
685 = loopM ? (mk_binaryTM sig M) (k - S n)
686 (mk_config ?? (〈q,bin2,ch,FS_crd sig〉)
687 (mk_tape ? [] (option_hd ? (bs@rs)) (tail ? (bs@rs)))). [2,3:@le_S //]
688 #sig #M #q #ch #k #n #Hk
689 cases (le_to_eq … Hk) #k0 #Hk0 >Hk0 >minus_tech
691 [ #rs #Hlt %{[]} % // cases rs //
692 | #n0 #IH #rs #Hn0 cases (IH (false::rs) ?) [|/2 by lt_S_to_lt/]
694 %{(bs@[false])} % [ <Hbs >length_append /2 by increasing_to_injective/ ]
695 >loopM_unfold >loop_S_false // >binaryTM_bin5_S
696 >associative_append normalize in match ([false]@?); <IH
697 >loopM_unfold @eq_f @eq_f cases rs //
701 lemma current_None_or_midtape :
702 ∀sig,t.current sig t = None sig ∨ ∃ls,c,rs.t = midtape sig ls c rs.
703 #sig * normalize /2/ #ls #c #rs %2 /4 by ex_intro/
706 lemma state_bin_lift_unfold :
707 ∀sig.∀M:TM sig.∀q:states sig M.
708 state_bin_lift sig M q = 〈q,bin0,None ?,FS_crd sig〉.// qed.
710 axiom current_tape_bin_list :
711 ∀sig,t.current sig t = None ? → current ? (tape_bin_lift sig t) = None ?.
713 lemma tape_bin_lift_unfold :
714 ∀sig,t. tape_bin_lift sig t =
715 mk_tape ? (rev_bin_list ? (left ? t)) (option_hd ? (opt_bin_char sig (current ? t)))
716 (tail ? (opt_bin_char sig (current ? t))@bin_list ? (right ? t)). //
719 lemma reverse_bin_char_list : ∀sig,c,l.
720 reverse ? (bin_char sig c)@rev_bin_list ? l = rev_bin_list ? (c::l). // qed.
722 lemma left_midtape : ∀sig,ls,c,rs.left ? (midtape sig ls c rs) = ls.// qed.
723 lemma current_midtape : ∀sig,ls,c,rs.current ? (midtape sig ls c rs) = Some ? c.// qed.
724 lemma right_midtape : ∀sig,ls,c,rs.right ? (midtape sig ls c rs) = rs.// qed.
725 lemma opt_bin_char_Some : ∀sig,c.opt_bin_char sig (Some ? c) = bin_char ? c.// qed.
727 lemma opt_cons_hd_tl : ∀A,l.option_cons A (option_hd ? l) (tail ? l) = l.
730 lemma le_tech : ∀a,b,c.a ≤ b → a * c ≤ b * c.
731 #a #b #c #H /2 by monotonic_le_times_r/
734 lemma iter_split : ∀T,f,m,n,x.
735 iter T f (m+n) x = iter T f m (iter T f n x).
736 #T #f #m #n elim n /2/
737 #n0 #IH #x <plus_n_Sm whd in ⊢ (??%(????%)); >IH %
740 lemma iter_tape_move_R : ∀T,n,ls,cs,rs.|cs| = n →
741 iter ? (λt0.tape_move T t0 R) n (mk_tape ? ls (option_hd ? (cs@rs)) (tail ? (cs@rs)))
742 = mk_tape ? (reverse ? cs@ls) (option_hd ? rs) (tail ? rs).
744 [ #ls * [| #c0 #cs0 #rs #H normalize in H; destruct (H) ] #rs #_ %
745 | #n0 #IH #ls * [ #rs #H normalize in H; destruct (H) ] #c #cs #rs #Hlen
747 >(?: (tape_move T (mk_tape T ls (option_hd T ((c::cs)@rs)) (tail T ((c::cs)@rs))) R)
748 = mk_tape ? (c::ls) (option_hd ? (cs@rs)) (tail ? (cs@rs))) in ⊢ (??(????%)?);
749 [| cases cs // cases rs // ] >IH
750 [ >reverse_cons >associative_append %
751 | normalize in Hlen; destruct (Hlen) % ]
755 lemma tail_tech : ∀T,l1,l2.O < |l1| → tail T (l1@l2) = tail ? l1@l2.
756 #T * normalize // #l2 #Hfalse @False_ind cases (not_le_Sn_O O) /2/
759 lemma hd_tech : ∀T,l1,l2.O < |l1| → option_hd T (l1@l2) = option_hd ? l1.
760 #T * normalize // #l2 #Hfalse @False_ind cases (not_le_Sn_O O) /2/
763 lemma iter_tape_move_l_nil : ∀T,n,rs.
764 iter ? (λt0.tape_move T t0 L) n (mk_tape ? [ ] (None ?) rs) =
765 mk_tape ? [ ] (None ?) rs.
766 #T #n #rs elim n // #n0 #IH <IH in ⊢ (???%); cases rs //
769 lemma iter_tape_move_L_left : ∀T,n,cs,rs. O < n →
770 iter ? (λt0.tape_move T t0 L) n
771 (mk_tape ? [ ] (option_hd ? cs) (tail ? cs@rs)) =
772 mk_tape ? [ ] (None ?) (cs@rs).
774 [ cases cs // cases rs //
775 | #m #_ whd in ⊢ (??%?); <(iter_tape_move_l_nil ? m) cases cs // cases rs // ]
778 lemma iter_tape_move_L : ∀T,n,ls,cs,rs.|cs| = n →
779 iter ? (λt0.tape_move T t0 L) n (mk_tape ? (reverse ? cs@ls) (option_hd ? rs) (tail ? rs))
780 = mk_tape ? ls (option_hd ? (cs@rs)) (tail ? (cs@rs)).
782 [ #ls * [| #c0 #cs0 #rs #H normalize in H; destruct (H) ] #rs #_ %
783 | #n0 #IH #ls #cs #rs @(list_elim_left … cs)
784 [ #H normalize in H; destruct (H) ] -cs
785 #c #cs #_ #Hlen >reverse_append whd in ⊢ (??%?);
786 >(?: tape_move T (mk_tape T ((reverse T [c]@reverse T cs)@ls) (option_hd T rs) (tail T rs)) L
787 = mk_tape ? (reverse T cs@ls) (option_hd ? (c::rs)) (tail ? (c::rs))) in ⊢ (??(????%)?);
789 [ >associative_append %
790 | >length_append in Hlen; normalize // ]
794 lemma binaryTM_loop :
797 loopM sig M i (mk_config ?? q t) = Some ? (mk_config ?? qf tf) →
798 ∃k.loopM ? (mk_binaryTM sig M) k
799 (mk_config ?? (state_bin_lift ? M q) (tape_bin_lift ? t)) =
800 Some ? (mk_config ?? (state_bin_lift ? M qf) (tape_bin_lift ? tf)).
802 [ #t #q #qf #tf #Hcrd change with (None ?) in ⊢ (??%?→?); #H destruct (H)
803 | -i #i #IH #t #q #tf #qf #Hcrd >loopM_unfold
804 lapply (refl ? (halt sig M (cstate ?? (mk_config ?? q t))))
805 cases (halt ?? q) in ⊢ (???%→?); #Hhalt
806 [ >(loop_S_true ??? (λc.halt ?? (cstate ?? c)) (mk_config ?? q t) Hhalt)
807 #H destruct (H) %{1} >loopM_unfold >loop_S_true // ]
808 (* interesting case: more than one step *)
809 >(loop_S_false ??? (λc.halt ?? (cstate ?? c)) (mk_config ?? q t) Hhalt)
810 <loopM_unfold >(config_expand ?? (step ???)) #Hloop
811 lapply (IH … Hloop) [@Hcrd] -IH * #k0 #IH <config_expand in Hloop; #Hloop
812 %{(7*(S (FS_crd sig)) + k0)}
814 >state_bin_lift_unfold cases (current_None_or_midtape ? t)
815 (* 0.1) current = None *)
816 [ (* #Hcur >state_bin_lift_unfold in ⊢ (??%?);
817 lapply (current_tape_bin_list … Hcur) #Hcur'
818 >binaryTM_phase0_None /2 by monotonic_lt_plus_l/
819 >(?: FS_crd sig + k0 = S (FS_crd sig + k0 - 1)) [|@daemon]
820 >loopM_unfold >loop_S_false // lapply (refl ? t) cases t in ⊢ (???%→?);
821 [4: #ls #c #rs normalize in ⊢ (%→?); #H destruct (H) normalize in Hcur; destruct (Hcur)
822 | #Ht >Ht >binaryTM_bin4_None // <loopM_unfold *)
824 | * #ls * #c * #rs #Ht >Ht >tape_bin_lift_unfold
825 >left_midtape >current_midtape >right_midtape >opt_bin_char_Some
826 >(binaryTM_phase0_midtape … Hhalt ? (refl ??)) [| // ]
827 >(?: 7*S (FS_crd sig) + k0 - S (FS_crd sig) = 6*S (FS_crd sig) + k0) [|/2 by plus_minus/]
830 [| cases (bin_list ? rs) normalize // #r0 #rs0 #H destruct (H)
831 | >length_reverse @daemon
833 >(?:6*S (FS_crd sig) + k0 - S (FS_crd sig) = 5*S (FS_crd sig) + k0) [|/2 by plus_minus/]
834 >reverse_reverse >opt_cons_hd_tl
835 cut (∃qn,chn,mv.〈qn,chn,mv〉 = trans ? M 〈q,Some ? c〉)
836 [ cases (trans ? M 〈q,Some ? c〉) * #qn #chn #mv /4 by ex_intro/ ]
837 * #qn * #chn * #mv cases chn -chn
838 [ (* no write! *) #Htrans >(binaryTM_phase2_None … Htrans) [2,3: //]
839 >iter_tape_move_R [|@daemon]
840 >(?:5*S (FS_crd sig) + k0 - S (FS_crd sig) = 4*S (FS_crd sig) + k0) [|/2 by plus_minus/]
842 [|//| cut (S (displ_of_move sig mv) ≤ 2*(S (FS_crd sig)))
844 | #H @(transitive_le ??? H) -H -Hcrd @(transitive_le ? (4*S (FS_crd sig))) /2 by le_plus_a/ ]
846 cut (∀sig,M,m,n,cfg,cfg'.m < n → loopM sig M m cfg = Some ? cfg' → loopM sig M n cfg = Some ? cfg') [@daemon]
847 #Hcut <(Hcut ??? (4*S (FS_crd sig) + k0 - S (displ_of_move sig mv)) ??? IH)
849 [ >(?:displ_of_move sig L = 2*FS_crd sig) //
851 @(transitive_le ? (pred (4*FS_crd sig+k0-2*FS_crd sig)))
852 [ >(?:4*FS_crd sig+k0-2*FS_crd sig = 2*FS_crd sig + k0)
853 [ cases Hcrd /2 by le_minus_to_plus, le_n/
855 >(commutative_times 4) >(commutative_times 2)
856 <distributive_times_minus //
858 | @monotonic_pred /2 by monotonic_le_minus_l/ ]
859 | whd in match (displ_of_move ??); @(transitive_le ? (4*1+k0-1))
861 | change with (pred (4*1+k0)) in ⊢ (?%?);
862 >eq_minus_S_pred <minus_n_O @monotonic_pred // ]
863 | >(?:displ_of_move sig N = FS_crd sig) //
865 @(transitive_le ? (pred (4*FS_crd sig+k0-1*FS_crd sig)))
866 [ >(?:4*FS_crd sig+k0-1*FS_crd sig = 3*FS_crd sig + k0)
867 [ cases Hcrd /2 by le_minus_to_plus, le_n/
869 >(commutative_times 4) >(commutative_times 1)
870 <distributive_times_minus //
872 | @monotonic_pred /2 by transitive_le, le_n/ ] ] ]
874 [ <state_bin_lift_unfold >Ht whd in match (step ???); <Htrans %
875 | (* must distinguish mv *)
876 cases mv in Htrans; #Htrans
877 [ >(?:displ_of_move ? L = FS_crd sig + FS_crd sig) [| normalize // ]
878 >iter_split >iter_tape_move_L [|@daemon] >Ht cases ls
879 [ normalize in match (rev_bin_list ??);
880 >hd_tech [|@daemon] >tail_tech [|@daemon]
881 >iter_tape_move_L_left // whd in match (step ???);
882 <Htrans whd in match (ctape ???);
883 >tape_bin_lift_unfold %
884 | #l0 #ls0 change with (reverse ? (bin_char ? l0)@rev_bin_list ? ls0) in match (rev_bin_list ??);
885 >iter_tape_move_L [|@daemon]
886 >hd_tech [|@daemon] >tail_tech [|@daemon]
887 whd in match (step ???); <Htrans whd in match (ctape ???);
888 >tape_bin_lift_unfold >left_midtape >current_midtape
889 >opt_bin_char_Some >right_midtape %
892 (mk_tape ? (reverse ? (bin_char ? c)@rev_bin_list ? ls)
893 (option_hd ? (bin_list ? rs)) (tail ? (bin_list ? rs)))
895 >reverse_bin_char_list <IH
896 >Ht >tape_bin_lift_unfold @eq_f3
897 whd in match (step ???); <Htrans cases rs //
898 #r0 #rs0 whd in match (ctape ???); >current_midtape >opt_bin_char_Some
899 [ <hd_tech in ⊢(???%); // @daemon
900 | >right_midtape <tail_tech // @daemon ]
901 | whd in match (displ_of_move ? N); >iter_tape_move_L [|@daemon]
902 >Ht whd in match (step ???); <Htrans whd in match (ctape ???);
903 >tape_bin_lift_unfold >left_midtape >current_midtape >right_midtape
904 >opt_bin_char_Some lapply Hcrd >(?:FS_crd sig = |bin_char ? c|) [| @daemon ]
905 cases (bin_char ? c) // #H normalize in H; @False_ind
906 cases (not_le_Sn_O O) /2/
915 theorem sem_binaryTM : ∀sig,M.
916 mk_binaryTM sig M ⊫ R_bin_lift ? (R_TM ? M (start ? M)).
917 #sig #M #t #i generalize in match t; -t
918 @(nat_elim1 … i) #m #IH #intape #outc #Hloop