include "turing/basic_machines.ma".
include "turing/if_machine.ma".
-definition mcl_states : FinSet → FinSet ≝ λalpha:FinSet.FinProd (initN 5) alpha.
-
-definition mcl0 : initN 5 ≝ mk_Sig ?? 0 (leb_true_to_le 1 5 (refl …)).
-definition mcl1 : initN 5 ≝ mk_Sig ?? 1 (leb_true_to_le 2 5 (refl …)).
-definition mcl2 : initN 5 ≝ mk_Sig ?? 2 (leb_true_to_le 3 5 (refl …)).
-definition mcl3 : initN 5 ≝ mk_Sig ?? 3 (leb_true_to_le 4 5 (refl …)).
-definition mcl4 : initN 5 ≝ mk_Sig ?? 4 (leb_true_to_le 5 5 (refl …)).
-
definition mcl_step ≝ λalpha:FinSet.λsep:alpha.
ifTM alpha (test_char ? (λc.¬c==sep))
(single_finalTM … (seq … (swap alpha sep) (move_l ?))) (nop ?) tc_true.
-
-(*
-definition mcl_step ≝
- λalpha:FinSet.λsep:alpha.
- mk_TM alpha (mcl_states alpha)
- (λp.let 〈q,a〉 ≝ p in
- let 〈q',b〉 ≝ q in
- let q' ≝ pi1 nat (λi.i<5) q' in (* perche' devo passare il predicato ??? *)
- match a with
- [ None ⇒ 〈〈mcl4,sep〉,None ?〉
- | Some a' ⇒
- match q' with
- [ O ⇒ (* qinit *)
- match a' == sep with
- [ true ⇒ 〈〈mcl4,sep〉,None ?〉
- | false ⇒ 〈〈mcl1,a'〉,Some ? 〈a',R〉〉 ]
- | S q' ⇒ match q' with
- [ O ⇒ (* q1 *)
- 〈〈mcl2,a'〉,Some ? 〈b,L〉〉
- | S q' ⇒ match q' with
- [ O ⇒ (* q2 *)
- 〈〈mcl3,sep〉,Some ? 〈b,L〉〉
- | S q' ⇒ match q' with
- [ O ⇒ (* qacc *)
- 〈〈mcl3,sep〉,None ?〉
- | S q' ⇒ (* qfail *)
- 〈〈mcl4,sep〉,None ?〉 ] ] ] ] ])
- 〈mcl0,sep〉
- (λq.let 〈q',a〉 ≝ q in q' == mcl3 ∨ q' == mcl4).
-
-lemma mcl_q0_q1 :
- ∀alpha:FinSet.∀sep,a,ls,a0,rs.
- a0 == sep = false →
- step alpha (mcl_step alpha sep)
- (mk_config ?? 〈mcl0,a〉 (mk_tape … ls (Some ? a0) rs)) =
- mk_config alpha (states ? (mcl_step alpha sep)) 〈mcl1,a0〉
- (tape_move_right alpha ls a0 rs).
-#alpha #sep #a *
-[ #a0 #rs #Ha0 whd in ⊢ (??%?);
- normalize in match (trans ???); >Ha0 %
-| #a1 #ls #a0 #rs #Ha0 whd in ⊢ (??%?);
- normalize in match (trans ???); >Ha0 %
-]
-qed.
-
-lemma mcl_q1_q2 :
- ∀alpha:FinSet.∀sep,a,ls,a0,rs.
- step alpha (mcl_step alpha sep)
- (mk_config ?? 〈mcl1,a〉 (mk_tape … ls (Some ? a0) rs)) =
- mk_config alpha (states ? (mcl_step alpha sep)) 〈mcl2,a0〉
- (tape_move_left alpha ls a rs).
-#alpha #sep #a #ls #a0 * //
-qed.
-
-lemma mcl_q2_q3 :
- ∀alpha:FinSet.∀sep,a,ls,a0,rs.
- step alpha (mcl_step alpha sep)
- (mk_config ?? 〈mcl2,a〉 (mk_tape … ls (Some ? a0) rs)) =
- mk_config alpha (states ? (mcl_step alpha sep)) 〈mcl3,sep〉
- (tape_move_left alpha ls a rs).
-#alpha #sep #a #ls #a0 * //
-qed.
-*)
-
definition Rmcl_step_true ≝
λalpha,sep,t1,t2.
∀a,b,ls,rs.
λalpha,sep,t1,t2.
right ? t1 ≠ [] → current alpha t1 ≠ None alpha →
current alpha t1 = Some alpha sep ∧ t2 = t1.
-(*
-lemma mcl_trans_init_sep:
- ∀alpha,sep,x.
- trans ? (mcl_step alpha sep) 〈〈mcl0,x〉,Some ? sep〉 = 〈〈mcl4,sep〉,None ?〉.
-#alpha #sep #x normalize >(\b ?) //
-qed.
-
-lemma mcl_trans_init_not_sep:
- ∀alpha,sep,x,y.y == sep = false →
- trans ? (mcl_step alpha sep) 〈〈mcl0,x〉,Some ? y〉 = 〈〈mcl1,y〉,Some ? 〈y,R〉〉.
-#alpha #sep #x #y #H1 normalize >H1 //
-qed.
-*)
lemma sem_mcl_step :
∀alpha,sep.
#Htapeb #Houttape #a #b #ls #rs #Hintape
>Hintape in Htapea; #Htapea cases (Htapea ? (refl …)) -Htapea
#Hbsep #Htapea % [@(\Pf (injective_notb ? false Hbsep))]
- @Houttape
+ @Houttape @Htapeb //
|#intape #outtape #tapea whd in ⊢ (%→%→%);
cases (current alpha intape)
[#_ #_ #_ * #Hfalse @False_ind @Hfalse %
|#c #H #Htapea #_ #_ cases (H c (refl …)) #csep #Hintape % //
- lapply (injective_notb ? true csep) -csep #csep >(\P csep)
+ lapply (injective_notb ? true csep) -csep #csep >(\P csep) //
]
-
-
-lemma sem_mcl_step :
- ∀alpha,sep.
- accRealize alpha (mcl_step alpha sep)
- 〈mcl3,sep〉 (Rmcl_step_true alpha sep) (Rmcl_step_false alpha sep).
-#alpha #sep cut (∀P:Prop.〈mcl4,sep〉=〈mcl3,sep〉→P)
- [#P whd in ⊢ ((??(???%?)(???%?))→?); #Hfalse destruct] #Hfalse
-*
-[@(ex_intro ?? 2)
- @(ex_intro … (mk_config ?? 〈mcl4,sep〉 (niltape ?)))
- % [% [whd in ⊢ (??%?);% |@Hfalse] |#H1 #H2 @False_ind @(absurd ?? H2) %]
-|#l0 #lt0 @(ex_intro ?? 2)
- @(ex_intro … (mk_config ?? 〈mcl4,sep〉 (leftof ? l0 lt0)))
- % [% [whd in ⊢ (??%?);% |@Hfalse] |#H1 #H2 #H3 @False_ind @(absurd ?? H3) %]
-|#r0 #rt0 @(ex_intro ?? 2)
- @(ex_intro … (mk_config ?? 〈mcl4,sep〉 (rightof ? r0 rt0)))
- % [% [whd in ⊢ (??%?);% |@Hfalse] |#H1 #H2 #H3 @False_ind @(absurd ?? H3) %]
-| #lt #c #rt cases (true_or_false (c == sep)) #Hc
- [ @(ex_intro ?? 2)
- @(ex_intro ?? (mk_config ?? 〈mcl4,sep〉 (midtape ? lt c rt)))
- % [ %
- [ >(\P Hc) >loopM_unfold >loop_S_false // >loop_S_true
- [ @eq_f whd in ⊢ (??%?); >mcl_trans_init_sep %
- |>(\P Hc) whd in ⊢(??(???(???%))?); >mcl_trans_init_sep % ]
- |@Hfalse]
- |#_ #H1 #H2 % // normalize >(\P Hc) % ]
- |@(ex_intro ?? 4) cases rt
- [ @ex_intro
- [|% [ %
- [ >loopM_unfold >loop_S_false // >mcl_q0_q1 //
- | normalize in ⊢ (%→?); @Hfalse]
- | normalize in ⊢ (%→?); #_ #H1 @False_ind @(absurd ?? H1) % ] ]
- | #r0 #rt0 @ex_intro
- [| % [ %
- [ >loopM_unfold >loop_S_false // >mcl_q0_q1 //
- | #_ #a #b #ls #rs #Hb destruct (Hb) %
- [ @(\Pf Hc)
- | >mcl_q1_q2 >mcl_q2_q3 cases ls normalize // ] ]
- | normalize in ⊢ (% → ?); * #Hfalse
- @False_ind /2/ ]
- ]
- ]
- ]
-]
+ ]
qed.
-
+
(* the move_char (variant c) machine *)
definition move_char_l ≝
λalpha,sep.whileTM alpha (mcl_step alpha sep) 〈mcl3,sep〉.