| @(eq_vec … (niltape ?)) #i0 #Hi0 cases (decidable_eq_nat i0 i) //
#Hi0i @sym_eq @Hnth_j @sym_not_eq // ] ]
qed.
+
(* move a single tape *)
-definition mmove_states ≝ initN 2.
+definition smove_states ≝ initN 2.
-definition mmove0 : mmove_states ≝ mk_Sig ?? 0 (leb_true_to_le 1 2 (refl …)).
-definition mmove1 : mmove_states ≝ mk_Sig ?? 1 (leb_true_to_le 2 2 (refl …)).
+definition smove0 : smove_states ≝ mk_Sig ?? 0 (leb_true_to_le 1 2 (refl …)).
+definition smove1 : smove_states ≝ mk_Sig ?? 1 (leb_true_to_le 2 2 (refl …)).
-definition trans_mmove ≝
- λi,sig,n,D.
- λp:mmove_states × (Vector (option sig) (S n)).
+definition trans_smove ≝
+ λsig,D.
+ λp:smove_states × (option sig).
let 〈q,a〉 ≝ p in match (pi1 … q) with
- [ O ⇒ 〈mmove1,change_vec ? (S n) (null_action ? n) (〈None ?,D〉) i〉
- | S _ ⇒ 〈mmove1,null_action sig n〉 ].
-
-definition mmove ≝
- λi,sig,n,D.
- mk_mTM sig n mmove_states (trans_mmove i sig n D)
- mmove0 (λq.q == mmove1).
-
+ [ O ⇒ 〈smove1,None sig, D〉
+ | S _ ⇒ 〈smove1,None sig, N〉 ].
+
+definition move ≝
+ λsig,D.mk_TM sig smove_states (trans_smove sig D) smove0 (λq.q == smove1).
+
+definition mmove ≝ λi,sig,n,D.inject_TM sig (move sig D) n i.
+
+definition Rmove ≝
+ λalpha,D,t1,t2. t2 = tape_move alpha t1 D.
+
+lemma sem_move_single :
+ ∀alpha,D.move alpha D ⊨ Rmove alpha D.
+#alpha #D #int %{2} %{(mk_config ? smove_states smove1 ?)} [| % % ]
+qed.
+
definition Rm_multi ≝
λalpha,n,i,D.λt1,t2:Vector ? (S n).
t2 = change_vec ? (S n) t1 (tape_move alpha (nth i ? t1 (niltape ?)) D) i.
-
+
lemma sem_move_multi :
∀alpha,n,i,D.i ≤ n →
mmove i alpha n D ⊨ Rm_multi alpha n i D.
-#alpha #n #i #D #Hin #int %{2}
-%{(mk_mconfig ? mmove_states n mmove1 ?)}
-[| %
- [ whd in ⊢ (??%?); @eq_f whd in ⊢ (??%?); @eq_f %
- | whd >tape_move_multi_def
- <(change_vec_same … (ctapes …) i (niltape ?))
- >pmap_change <tape_move_multi_def >tape_move_null_action % ] ]
- qed.
+#alpha #n #i #D #Hin #ta cases (sem_inject … Hin (sem_move_single alpha D) ta)
+#k * #outc * #Hloop * whd in ⊢ (%→?); #Htb1 #Htb2 %{k} %{outc} % [ @Hloop ]
+whd @(eq_vec … (niltape ?)) #i0 #Hi0 cases (decidable_eq_nat i0 i) #Hi0i
+[ >Hi0i >Htb1 >nth_change_vec //
+| >nth_change_vec_neq [|@sym_not_eq //] <Htb2 // @sym_not_eq // ]
+qed.
(* simple copy with no move *)
definition copy_states ≝ initN 3.
-(********************** look_ahead test *************************)
-
-definition mtestR ≝ λsig,i,n,test.
- (mmove i sig n R) ·
- (ifTM ?? (inject_TM ? (test_char ? test) n i)
- (single_finalTM ?? (mmove i sig n L))
- (mmove i sig n L) tc_true).
-
-(* underspecified *)
-definition RmtestR_true ≝ λsig,i,n,test.λt1,t2:Vector ? n.
- ∀ls,c,c1,rs.
- nth i ? t1 (niltape ?) = midtape sig ls c (c1::rs) →
- t1 = t2 ∧ (test c1 = true).
-
-definition RmtestR_false ≝ λsig,i,n,test.λt1,t2:Vector ? n.
- ∀ls,c,c1,rs.
- nth i ? t1 (niltape ?) = midtape sig ls c (c1::rs) →
- t1 = t2 ∧ (test c1 = false).
-
-definition mtestR_acc: ∀sig,i,n,test.states ?? (mtestR sig i n test).
-#sig #i #n #test @inr @inr @inl @inr @start_nop
-qed.
-
-lemma sem_mtestR: ∀sig,i,n,test. i ≤ n →
- mtestR sig i n test ⊨
- [mtestR_acc sig i n test:
- RmtestR_true sig i (S n) test, RmtestR_false sig i (S n) test].
-#sig #i #n #test #Hlein
-@(acc_sem_seq_app sig n … (sem_move_multi … R Hlein)
- (acc_sem_if sig n ????????
- (sem_test_char_multi sig test n i Hlein)
- (sem_move_multi … L Hlein)
- (sem_move_multi … L Hlein)))
- [#t1 #t2 #t3 whd in ⊢ (%→?); #Hmove * #tx * whd in ⊢ (%→?); * *
- #cx #Hcx #Htx #Ht2 #ls #c #c1 #rs #Ht1
- >Ht1 in Hmove; whd in match (tape_move ???); #Ht3
- >Ht3 in Hcx; >nth_change_vec [|@le_S_S //] * whd in ⊢ (??%?→?);
- #Hsome destruct (Hsome) #Htest % [2:@Htest]
- >Htx in Ht2; whd in ⊢ (%→?); #Ht2 @(eq_vec … (niltape ?))
- #j #lejn cases (true_or_false (eqb i j)) #Hij
- [lapply lejn <(eqb_true_to_eq … Hij) #lein >Ht2 >nth_change_vec [2://]
- >Ht3 >nth_change_vec >Ht1 //
- |lapply (eqb_false_to_not_eq … Hij) #Hneq >Ht2 >nth_change_vec_neq [2://]
- >Ht3 >nth_change_vec_neq //
- ]
- |#t1 #t2 #t3 whd in ⊢ (%→?); #Hmove * #tx * whd in ⊢ (%→?); *
- #Hcx #Heqtx #Htx #ls #c #c1 #rs #Ht1
- >Ht1 in Hmove; whd in match (tape_move ???); #Ht3
- >Ht3 in Hcx; >nth_change_vec [2:@le_S_S //] #Hcx lapply (Hcx ? (refl ??))
- #Htest % // @(eq_vec … (niltape ?))
- #j #lejn cases (true_or_false (eqb i j)) #Hij
- [lapply lejn <(eqb_true_to_eq … Hij) #lein >Htx >nth_change_vec [2://]
- >Heqtx >Ht3 >nth_change_vec >Ht1 //
- |lapply (eqb_false_to_not_eq … Hij) #Hneq >Htx >nth_change_vec_neq [2://]
- >Heqtx >Ht3 >nth_change_vec_neq //
- ]
- ]
-qed.