Theorem: Turing.TM1to1.tr_respects
File: Mathlib/Computability/TuringMachine.lean

Proof steps:
state_before: Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
l₁ : Option Λ
v : σ
T : Tape Γ
⊢ FRespects (step (tr enc dec M)) (trCfg enc enc₀) (trCfg enc enc₀ { l := l₁, var := v, Tape := T })
    (step M { l := l₁, var := v, Tape := T })
state_after: case intro.intro
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
l₁ : Option Λ
v : σ
L R : ListBlank Γ
⊢ FRespects (step (tr enc dec M)) (trCfg enc enc₀) (trCfg enc enc₀ { l := l₁, var := v, Tape := Tape.mk' L R })
    (step M { l := l₁, var := v, Tape := Tape.mk' L R })
tactic: obtain ⟨L, R, rfl⟩ := T.exists_mk'
state_before: case intro.intro
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
l₁ : Option Λ
v : σ
L R : ListBlank Γ
⊢ FRespects (step (tr enc dec M)) (trCfg enc enc₀) (trCfg enc enc₀ { l := l₁, var := v, Tape := Tape.mk' L R })
    (step M { l := l₁, var := v, Tape := Tape.mk' L R })
state_after: case intro.intro.none
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L R : ListBlank Γ
⊢ FRespects (step (tr enc dec M)) (trCfg enc enc₀) (trCfg enc enc₀ { l := none, var := v, Tape := Tape.mk' L R })
    (step M { l := none, var := v, Tape := Tape.mk' L R })

case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L R : ListBlank Γ
l₁ : Λ
⊢ FRespects (step (tr enc dec M)) (trCfg enc enc₀) (trCfg enc enc₀ { l := some l₁, var := v, Tape := Tape.mk' L R })
    (step M { l := some l₁, var := v, Tape := Tape.mk' L R })
tactic: cases' l₁ with l₁
state_before: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L R : ListBlank Γ
l₁ : Λ
⊢ FRespects (step (tr enc dec M)) (trCfg enc enc₀) (trCfg enc enc₀ { l := some l₁, var := v, Tape := Tape.mk' L R })
    (step M { l := some l₁, var := v, Tape := Tape.mk' L R })
state_after: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L R : ListBlank Γ
l₁ : Λ
⊢ ∀ (q : Stmt₁) (R : ListBlank Γ),
    Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
      (trCfg enc enc0 (stepAux q v (Tape.mk' L R)))
tactic: suffices ∀ q R, Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
        (trCfg enc enc0 (stepAux q v (Tape.mk' L R))) by
      refine TransGen.head' rfl ?_
      rw [trTape_mk']
      exact this _ R
state_before: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L R : ListBlank Γ
l₁ : Λ
⊢ ∀ (q : Stmt₁) (R : ListBlank Γ),
    Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
      (trCfg enc enc0 (stepAux q v (Tape.mk' L R)))
state_after: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L : ListBlank Γ
⊢ ∀ (q : Stmt₁) (R : ListBlank Γ),
    Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
      (trCfg enc enc0 (stepAux q v (Tape.mk' L R)))
tactic: clear R l₁
state_before: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L : ListBlank Γ
⊢ ∀ (q : Stmt₁) (R : ListBlank Γ),
    Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
      (trCfg enc enc0 (stepAux q v (Tape.mk' L R)))
state_after: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L : ListBlank Γ
q : Stmt₁
R : ListBlank Γ
⊢ Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
    (trCfg enc enc0 (stepAux q v (Tape.mk' L R)))
tactic: intro q R
state_before: case intro.intro.some
Γ : Type u_1
inst✝² : Inhabited Γ
Λ : Type u_2
inst✝¹ : Inhabited Λ
σ : Type u_3
inst✝ : Inhabited σ
n : ℕ
enc : Γ → Vector Bool n
dec : Vector Bool n → Γ
enc0 : enc default = Vector.replicate n false
M : Λ → Stmt₁
encdec : ∀ (a : Γ), dec (enc a) = a
enc₀ : enc default = Vector.replicate n false
x✝ : Cfg₁
v : σ
L : ListBlank Γ
q : Stmt₁
R : ListBlank Γ
⊢ Reaches (step (tr enc dec M)) (stepAux (trNormal dec q) v (trTape' enc0 L R))
    (trCfg enc enc0 (stepAux q v (Tape.mk' L R)))
state_after: no goals
tactic: induction q generalizing v L R with
    | move d q IH =>
      cases d <;>
          simp only [trNormal, iterate, stepAux_move, stepAux, ListBlank.head_cons,
            Tape.move_left_mk', ListBlank.cons_head_tail, ListBlank.tail_cons,
            trTape'_move_left enc0, trTape'_move_right enc0] <;>
        apply IH
    | write f q IH =>
      simp only [trNormal, stepAux_read dec enc0 encdec, stepAux]
      refine ReflTransGen.head rfl ?_
      obtain ⟨a, R, rfl⟩ := R.exists_cons
      rw [tr, Tape.mk'_head, stepAux_write, ListBlank.head_cons, stepAux_move,
        trTape'_move_left enc0, ListBlank.head_cons, ListBlank.tail_cons, Tape.write_mk']
      apply IH
    | load a q IH =>
      simp only [trNormal, stepAux_read dec enc0 encdec]
      apply IH
    | branch p q₁ q₂ IH₁ IH₂ =>
      simp only [trNormal, stepAux_read dec enc0 encdec, stepAux, Tape.mk'_head]
      cases p R.head v <;> [apply IH₂; apply IH₁]
    | goto l =>
      simp only [trNormal, stepAux_read dec enc0 encdec, stepAux, trCfg, trTape_mk']
      apply ReflTransGen.refl
    | halt =>
      simp only [trNormal, stepAux, trCfg, stepAux_move, trTape'_move_left enc0,
        trTape'_move_right enc0, trTape_mk']
      apply ReflTransGen.refl