mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Data.List.ReduceOption

Goal state before:
pp: α : Type u_1
l : List (Option α)
⊢ l.reduceOption.length < l.length ↔ none ∈ l

Tactic:
by
  rw [Nat.lt_iff_le_and_ne, and_iff_right (reduceOption_length_le l), Ne,
    reduceOption_length_eq_iff]
  induction l
  · simp
  · grind [cases Option]

Goal state after:
Module: Mathlib.Computability.NFA

Goal state before:
pp: α : Type u
σ : Type v
M : NFA α σ
x : List α
⊢ x ∈ M.toDFA.accepts ↔ ∃ S ∈ M.accept, S ∈ M.evalFrom M.start x

Tactic:
DFA.mem_accepts

Goal state after:
α : Type u
σ : Type v
M : NFA α σ
x : List α
⊢ M.toDFA.eval x ∈ M.toDFA.accept ↔ ∃ S ∈ M.accept, S ∈ M.evalFrom M.start x
Module: Mathlib.Computability.EpsilonNFA

Goal state before:
pp: α : Type u
σ : Type v
M : NFA α σ
⊢ {x | ∃ S ∈ M.toεNFA.accept, S ∈ M.toεNFA.evalFrom M.toεNFA.start x} = M.accepts

Tactic:
toεNFA_evalFrom_match

Goal state after:
α : Type u
σ : Type v
M : NFA α σ
⊢ {x | ∃ S ∈ M.toεNFA.accept, S ∈ M.evalFrom M.toεNFA.start x} = M.accepts
Module: Mathlib.Computability.MyhillNerode

Goal state before:
pp: α : Type u
L : Language α
x : List α
⊢ x ∈ L.toDFA.accepts ↔ x ∈ L

Tactic:
DFA.mem_accepts

Goal state after:
α : Type u
L : Language α
x : List α
⊢ L.toDFA.eval x ∈ L.toDFA.accept ↔ x ∈ L
Module: Mathlib.Computability.RE

Goal state before:
pp: α : Type u_1
inst✝ : Primcodable α
p : α → Prop
⊢ (∃ f, Computable f ∧ p = fun a ↦ f a = true) → ComputablePred p

Tactic:
rintro ⟨f, h, rfl⟩; exact ⟨by infer_instance, by simpa using h⟩

Goal state after:
Module: Mathlib.Computability.TuringMachine.Tape

Goal state before:
pp: case inr.inr.H
Γ : Type u_1
i : Inhabited Γ
L₁ L₂ : ListBlank Γ
l₁ l₂ : List Γ
H : ∀ (i_1 : ℕ), (mk l₁).nth i_1 = (mk l₂).nth i_1
this :
  ∀ {Γ : Type u_1} [i : Inhabited Γ] {L₁ L₂ : ListBlank Γ} (l₁ l₂ : List Γ),
    (∀ (i_1 : ℕ), (mk l₁).nth i_1 = (mk l₂).nth i_1) → l₁.length ≤ l₂.length → mk l₁ = mk l₂
h : ¬l₁.length ≤ l₂.length
h✝ : l₂.length ≤ l₁.length
i✝ : ℕ
⊢ (mk l₂).nth i✝ = (mk l₁).nth i✝

Tactic:
rw [H]

Goal state after:
Module: Mathlib.Computability.Reduce

Goal state before:
pp: α : Type u
inst✝³ : Primcodable α
inst✝² : Inhabited α
β : Type v
inst✝¹ : Primcodable β
inst✝ : Inhabited β
p : α → Prop
q : β → Prop
⊢ of p = of q ↔ ManyOneEquiv p q

Tactic:
by
  rw [of, of, Quotient.eq'']
  simp

Goal state after:
Module: Mathlib.Computability.TuringMachine.PostTuringMachine

Goal state before:
pp: Γ : Type u_1
Λ : Type u_2
σ : Type u_3
n : ℕ
S : Finset (Λ' Γ Λ σ)
d : Dir
q : Stmt Bool (Λ' Γ Λ σ) σ
i : ℕ
⊢ SupportsStmt S ((Stmt.move d)^[i] q) = SupportsStmt S q

Tactic:
induction i generalizing q <;> simp only [*, iterate]

Goal state after:
case succ
Γ : Type u_1
Λ : Type u_2
σ : Type u_3
n : ℕ
S : Finset (Λ' Γ Λ σ)
d : Dir
n✝ : ℕ
a✝ : ∀ {q : Stmt Bool (Λ' Γ Λ σ) σ}, SupportsStmt S ((Stmt.move d)^[n✝] q) = SupportsStmt S q
q : Stmt Bool (Λ' Γ Λ σ) σ
⊢ SupportsStmt S (Stmt.move d q) = SupportsStmt S q
Module: Mathlib.Computability.TuringMachine.PostTuringMachine

Goal state before:
pp: Γ : Type u_1
Λ : Type u_2
σ : Type u_3
n : ℕ
enc : Γ → List.Vector Bool n
dec : List.Vector Bool n → Γ
M : Λ → Stmt Γ Λ σ
inst✝ : Inhabited Γ
enc0 : enc default = List.Vector.replicate n false
L R : ListBlank Γ
⊢ Tape Bool

Tactic:
refine
      Tape.mk' (L.flatMap (fun x ↦ (enc x).toList.reverse) ⟨n, ?_⟩)
        (R.flatMap (fun x ↦ (enc x).toList) ⟨n, ?_⟩) <;>
    simp only [enc0, List.Vector.replicate, List.reverse_replicate, Bool.default_bool,
      List.Vector.toList_mk]

Goal state after:
Module: Mathlib.Computability.TuringMachine.StackTuringMachine

Goal state before:
pp: K : Type u_1
Γ : K → Type u_2
L : ListBlank ((k : K) → Option (Γ k))
n : ℕ
| ((addBottom L).nth n).2 = L.nth n

Tactic:
rhs; rw [← addBottom_map L, ListBlank.nth_map]

Goal state after:
K : Type u_1
Γ : K → Type u_2
L : ListBlank ((k : K) → Option (Γ k))
n : ℕ
| { f := Prod.snd, map_pt' := ⋯ }.f ((addBottom L).nth n)
Module: Mathlib.Computability.TuringMachine.PostTuringMachine

Goal state before:
pp: case some.load
Γ : Type u_1
Λ : Type u_2
σ : Type u_3
n : ℕ
enc : Γ → List.Vector Bool n
dec : List.Vector Bool n → Γ
M : Λ → Stmt Γ Λ σ
inst✝ : Inhabited Γ
enc0 : enc default = List.Vector.replicate n false
encdec : ∀ (a : Γ), dec (enc a) = a
x✝ : Cfg Γ Λ σ
a : Γ → σ → σ
q : Stmt Γ Λ σ
IH :
  ∀ (v : σ) (L 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)))
v : σ
L R : ListBlank Γ
⊢ Reaches (step (tr enc dec M)) (stepAux (trNormal dec (Stmt.load a q)) v (trTape' enc0 L R))
    (trCfg enc enc0 (stepAux (Stmt.load a q) v (Tape.mk' L R)))

Tactic:
simp only [trNormal, stepAux_read dec enc0 encdec]
      apply IH

Goal state after:
Module: Mathlib.Data.Num.Lemmas

Goal state before:
pp: case zero
n : ℕ
⊢ ↑(zero <<< n) = ↑zero <<< n

Tactic:
dsimp only [← shiftl_eq_shiftLeft, shiftl]

Goal state after:
case zero
n : ℕ
⊢ ↑0 = ↑zero <<< n
Module: Mathlib.Data.Num.Lemmas

Goal state before:
pp: case pos
n : ℕ
a✝ : PosNum
⊢ ↑(pos a✝ <<< n) = ↑(pos a✝) <<< n

Tactic:
dsimp only [← shiftl_eq_shiftLeft, shiftl]

Goal state after:
case pos
n : ℕ
a✝ : PosNum
⊢ ↑(pos (a✝ <<< n)) = ↑(pos a✝) <<< n
Module: Mathlib.Computability.TuringMachine.StackTuringMachine

Goal state before:
pp: case pos
K : Type u_1
Γ : K → Type u_2
Λ : Type u_3
σ : Type u_4
inst✝ : DecidableEq K
k : K
q : TM1.Stmt (Γ' K Γ) (Λ' K Γ Λ σ) σ
v : σ
S : (k : K) → List (Γ k)
L : ListBlank ((k : K) → Option (Γ k))
hL : ∀ (k : K), ListBlank.map (proj k) L = ListBlank.mk (List.map some (S k)).reverse
f : σ → Γ k
this :
  ∀ (L R : ListBlank (Γ' K Γ)) (n : ℕ),
    Tape.write ((R.nth n).1, update (R.nth n).2 k (some (f v))) ((Tape.move Dir.right)^[n] (Tape.mk' L R)) =
      (Tape.move Dir.right)^[n] (Tape.mk' L (ListBlank.modifyNth (fun a ↦ (a.1, update a.2 k (some (f v)))) n R))
k' : K
i : ℕ
h' : ¬k' = k
h✝ : i = (S k).length
⊢ update (L.nth i) k (some (f v)) k' = (ListBlank.mk (List.map some (update S k (f v :: S k) k')).reverse).nth i

Tactic:
rw [Function.update_of_ne h', ← proj_map_nth, hL]

Goal state after:
case pos
K : Type u_1
Γ : K → Type u_2
Λ : Type u_3
σ : Type u_4
inst✝ : DecidableEq K
k : K
q : TM1.Stmt (Γ' K Γ) (Λ' K Γ Λ σ) σ
v : σ
S : (k : K) → List (Γ k)
L : ListBlank ((k : K) → Option (Γ k))
hL : ∀ (k : K), ListBlank.map (proj k) L = ListBlank.mk (List.map some (S k)).reverse
f : σ → Γ k
this :
  ∀ (L R : ListBlank (Γ' K Γ)) (n : ℕ),
    Tape.write ((R.nth n).1, update (R.nth n).2 k (some (f v))) ((Tape.move Dir.right)^[n] (Tape.mk' L R)) =
      (Tape.move Dir.right)^[n] (Tape.mk' L (ListBlank.modifyNth (fun a ↦ (a.1, update a.2 k (some (f v)))) n R))
k' : K
i : ℕ
h' : ¬k' = k
h✝ : i = (S k).length
⊢ (ListBlank.mk (List.map some (S k')).reverse).nth i =
    (ListBlank.mk (List.map some (update S k (f v :: S k) k')).reverse).nth i
Module: Mathlib.Computability.TuringMachine.StackTuringMachine

Goal state before:
pp: case neg
K : Type u_1
Γ : K → Type u_2
Λ : Type u_3
σ : Type u_4
inst✝ : DecidableEq K
k : K
q : TM1.Stmt (Γ' K Γ) (Λ' K Γ Λ σ) σ
v : σ
S : (k : K) → List (Γ k)
L : ListBlank ((k : K) → Option (Γ k))
hL : ∀ (k : K), ListBlank.map (proj k) L = ListBlank.mk (List.map some (S k)).reverse
f : σ → Γ k
this :
  ∀ (L R : ListBlank (Γ' K Γ)) (n : ℕ),
    Tape.write ((R.nth n).1, update (R.nth n).2 k (some (f v))) ((Tape.move Dir.right)^[n] (Tape.mk' L R)) =
      (Tape.move Dir.right)^[n] (Tape.mk' L (ListBlank.modifyNth (fun a ↦ (a.1, update a.2 k (some (f v)))) n R))
k' : K
i : ℕ
h' : ¬k' = k
h✝ : ¬i = (S k).length
⊢ L.nth i k' = (ListBlank.mk (List.map some (update S k (f v :: S k) k')).reverse).nth i

Tactic:
rw [Function.update_of_ne h', ← proj_map_nth, hL]

Goal state after:
Module: Mathlib.Computability.TuringMachine.StackTuringMachine

Goal state before:
pp: case pos
K : Type u_1
Γ : K → Type u_2
Λ : Type u_3
σ : Type u_4
inst✝ : DecidableEq K
k : K
q : TM1.Stmt (Γ' K Γ) (Λ' K Γ Λ σ) σ
v : σ
S : (k : K) → List (Γ k)
L : ListBlank ((k : K) → Option (Γ k))
hL : ∀ (k : K), ListBlank.map (proj k) L = ListBlank.mk (List.map some (S k)).reverse
f : σ → Option (Γ k) → σ
hd : Γ k
tl : List (Γ k)
e : S k = hd :: tl
k' : K
i : ℕ
h' : ¬k' = k
h✝ : i = tl.length
⊢ update (L.nth i) k none k' = (ListBlank.mk (List.map some (update S k (hd :: tl).tail k')).reverse).nth i

Tactic:
rw [Function.update_of_ne h', ← proj_map_nth, hL]

Goal state after:
case pos
K : Type u_1
Γ : K → Type u_2
Λ : Type u_3
σ : Type u_4
inst✝ : DecidableEq K
k : K
q : TM1.Stmt (Γ' K Γ) (Λ' K Γ Λ σ) σ
v : σ
S : (k : K) → List (Γ k)
L : ListBlank ((k : K) → Option (Γ k))
hL : ∀ (k : K), ListBlank.map (proj k) L = ListBlank.mk (List.map some (S k)).reverse
f : σ → Option (Γ k) → σ
hd : Γ k
tl : List (Γ k)
e : S k = hd :: tl
k' : K
i : ℕ
h' : ¬k' = k
h✝ : i = tl.length
⊢ (ListBlank.mk (List.map some (S k')).reverse).nth i =
    (ListBlank.mk (List.map some (update S k (hd :: tl).tail k')).reverse).nth i
Module: Mathlib.Computability.TuringMachine.StackTuringMachine

Goal state before:
pp: case neg
K : Type u_1
Γ : K → Type u_2
Λ : Type u_3
σ : Type u_4
inst✝ : DecidableEq K
k : K
q : TM1.Stmt (Γ' K Γ) (Λ' K Γ Λ σ) σ
v : σ
S : (k : K) → List (Γ k)
L : ListBlank ((k : K) → Option (Γ k))
hL : ∀ (k : K), ListBlank.map (proj k) L = ListBlank.mk (List.map some (S k)).reverse
f : σ → Option (Γ k) → σ
hd : Γ k
tl : List (Γ k)
e : S k = hd :: tl
k' : K
i : ℕ
h' : ¬k' = k
h✝ : ¬i = tl.length
⊢ L.nth i k' = (ListBlank.mk (List.map some (update S k (hd :: tl).tail k')).reverse).nth i

Tactic:
rw [Function.update_of_ne h', ← proj_map_nth, hL]

Goal state after:
Module: Mathlib.Computability.TuringMachine.Config

Goal state before:
pp: case case
k' : Cont
a✝¹ a✝ : Code
a_ih✝¹ : ∀ (k : Cont) (v : List ℕ), stepNormal a✝¹ (k.then k') v = (stepNormal a✝¹ k v).then k'
a_ih✝ : ∀ (k : Cont) (v : List ℕ), stepNormal a✝ (k.then k') v = (stepNormal a✝ k v).then k'
k : Cont
v : List ℕ
⊢ Nat.rec ((stepNormal a✝¹ k v.tail).then k') (fun y x ↦ (stepNormal a✝ k (y :: v.tail)).then k') v.headI =
    (Nat.rec (stepNormal a✝¹ k v.tail) (fun y x ↦ stepNormal a✝ k (y :: v.tail)) v.headI).then k'

Tactic:
cases v.headI <;> simp only [Nat.rec_zero]

Goal state after:
Module: Mathlib.Computability.TuringMachine.ToPartrec

Goal state before:
pp: case cons.nil
p : Γ' → Bool
k₁ k₂ : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
h₁ : k₁ ≠ k₂
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k₁) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.move p k₁ k₂ q), var := s, stk := S }
        { l := some q, var := o, stk := update (update S k₁ L₂) k₂ (L₁.reverseAux (S k₂)) }
s : Option Γ'
S : K' → List Γ'
e : splitAtPred p (S k₁) = (a :: L₁, o, L₂)
e₁ : S k₁ = []
⊢ TransGen (fun a b ↦ b ∈ TM2.step tr a)
    (bif
        match [].head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := [].head?, stk := update S k₁ [].tail }
    else
      { l := some (Λ'.move p k₁ k₂ q), var := [].head?,
        stk := update (update S k₁ [].tail) k₂ ([].head?.getD default :: update S k₁ [].tail k₂) })
    { l := some q, var := o, stk := update (update S k₁ L₂) k₂ ((a :: L₁).reverseAux (S k₂)) }

Tactic:
e₁,

Goal state after:
case cons.nil
p : Γ' → Bool
k₁ k₂ : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
h₁ : k₁ ≠ k₂
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k₁) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.move p k₁ k₂ q), var := s, stk := S }
        { l := some q, var := o, stk := update (update S k₁ L₂) k₂ (L₁.reverseAux (S k₂)) }
s : Option Γ'
S : K' → List Γ'
e : splitAtPred p [] = (a :: L₁, o, L₂)
e₁ : S k₁ = []
⊢ TransGen (fun a b ↦ b ∈ TM2.step tr a)
    (bif
        match [].head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := [].head?, stk := update S k₁ [].tail }
    else
      { l := some (Λ'.move p k₁ k₂ q), var := [].head?,
        stk := update (update S k₁ [].tail) k₂ ([].head?.getD default :: update S k₁ [].tail k₂) })
    { l := some q, var := o, stk := update (update S k₁ L₂) k₂ ((a :: L₁).reverseAux (S k₂)) }
Module: Mathlib.Computability.TuringMachine.ToPartrec

Goal state before:
pp: case cons.cons
p : Γ' → Bool
k₁ k₂ : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
h₁ : k₁ ≠ k₂
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k₁) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.move p k₁ k₂ q), var := s, stk := S }
        { l := some q, var := o, stk := update (update S k₁ L₂) k₂ (L₁.reverseAux (S k₂)) }
s : Option Γ'
S : K' → List Γ'
e : splitAtPred p (S k₁) = (a :: L₁, o, L₂)
a' : Γ'
Sk : List Γ'
e₁ : S k₁ = a' :: Sk
⊢ TransGen (fun a b ↦ b ∈ TM2.step tr a)
    (bif
        match (a' :: Sk).head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := (a' :: Sk).head?, stk := update S k₁ (a' :: Sk).tail }
    else
      { l := some (Λ'.move p k₁ k₂ q), var := (a' :: Sk).head?,
        stk :=
          update (update S k₁ (a' :: Sk).tail) k₂ ((a' :: Sk).head?.getD default :: update S k₁ (a' :: Sk).tail k₂) })
    { l := some q, var := o, stk := update (update S k₁ L₂) k₂ ((a :: L₁).reverseAux (S k₂)) }

Tactic:
e₁,

Goal state after:
case cons.cons
p : Γ' → Bool
k₁ k₂ : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
h₁ : k₁ ≠ k₂
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k₁) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.move p k₁ k₂ q), var := s, stk := S }
        { l := some q, var := o, stk := update (update S k₁ L₂) k₂ (L₁.reverseAux (S k₂)) }
s : Option Γ'
S : K' → List Γ'
a' : Γ'
Sk : List Γ'
e : splitAtPred p (a' :: Sk) = (a :: L₁, o, L₂)
e₁ : S k₁ = a' :: Sk
⊢ TransGen (fun a b ↦ b ∈ TM2.step tr a)
    (bif
        match (a' :: Sk).head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := (a' :: Sk).head?, stk := update S k₁ (a' :: Sk).tail }
    else
      { l := some (Λ'.move p k₁ k₂ q), var := (a' :: Sk).head?,
        stk :=
          update (update S k₁ (a' :: Sk).tail) k₂ ((a' :: Sk).head?.getD default :: update S k₁ (a' :: Sk).tail k₂) })
    { l := some q, var := o, stk := update (update S k₁ L₂) k₂ ((a :: L₁).reverseAux (S k₂)) }
Module: Mathlib.Topology.Separation.Profinite

Goal state before:
pp: X : Type u_4
I✝ : Type u_5
inst✝⁵ : TopologicalSpace X
inst✝⁴ : CompactSpace X
inst✝³ : T2Space X
inst✝² : TotallyDisconnectedSpace X
inst✝¹ : Finite I✝
I : Type u_5
inst✝ : Fintype I
IH :
  ∀ {Z D : I → Set X},
    (∀ (i : I), IsClosed[inst✝⁵] (Z i)) →
      (∀ (i : I), IsClopen (D i)) →
        (∀ (i : I), Z i ⊆ D i) →
          univ.PairwiseDisjoint Z →
            ∃ C,
              (∀ (i : I), IsClopen (C i)) ∧
                (∀ (i : I), Z i ⊆ C i) ∧ (∀ (i : I), C i ⊆ D i) ∧ ⋃ i, D i ⊆ ⋃ i, C i ∧ univ.PairwiseDisjoint C
Z D : Option I → Set X
Z_closed : ∀ (i : Option I), IsClosed[inst✝⁵] (Z i)
D_clopen : ∀ (i : Option I), IsClopen (D i)
Z_subset_D : ∀ (i : Option I), Z i ⊆ D i
Z_disj : univ.PairwiseDisjoint Z
Z' : I → Set X := fun i ↦ Z (some i)
Z'_closed : ∀ (i : I), IsClosed[inst✝⁵] (Z (some i))
Z'_disj : univ.PairwiseDisjoint (Z ∘ some)
U : Set X := D none \ ⋃ i, Z (some i)
U_open : IsOpen[inst✝⁵] U
Z0_subset_U : Z none ⊆ U
V : Set X
V_clopen : IsClopen V
Z0_subset_V : Z none ⊆ V
V_subset_U : V ⊆ U
V_subset_D0 : V ⊆ D none
D' : I → Set X := fun i ↦ D (some i) \ V
D'_clopen : ∀ (i : I), IsClopen (D' i)
Z'_subset_D' : ∀ (i : I), Z' i ⊆ D' i
C' : I → Set X
C'_clopen : ∀ (i : I), IsClopen (C' i)
Z'_subset_C' : ∀ (i : I), Z (some i) ⊆ C' i
C'_subset_D' : ∀ (i : I), C' i ⊆ D' i
C'_cover_D' : ⋃ i, D' i ⊆ ⋃ i, C' i
C'_disj : univ.PairwiseDisjoint C'
C0 : Set X := D none \ ⋃ i, C' i
this : IsClopen C0
⊢ Z none ⊆ D none ∧ Disjoint (Z none) (⋃ i, C' i)

Tactic:
exact ⟨by grind, Disjoint.mono_left Z0_subset_V (by simp; grind)⟩

Goal state after:
Module: Mathlib.Topology.Category.Profinite.Basic

Goal state before:
pp: X Y : Profinite
f : X ⟶ Y
y : ↑Y.toTop
hy : ∀ (a : ↑X.toTop), (ConcreteCategory.hom f) a ≠ y
hf : Epi f
C : Set ((fun X ↦ ↑X.toTop) Y) := Set.range ⇑(ConcreteCategory.hom f)
hC : IsClosed C
U : Set ((fun X ↦ ↑X.toTop) Y) := Cᶜ
y' : (fun X ↦ ↑X.toTop) X
hy' : (ConcreteCategory.hom f) y' = y
⊢ False

Tactic:
exact hy y' hy'

Goal state after:
Module: Mathlib.Computability.TuringMachine.ToPartrec

Goal state before:
pp: case nil.cons.true
p : Γ' → Bool
k : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
s : Option Γ'
S : K' → List Γ'
a : Γ'
Sk : List Γ'
e₁ : some a = o
e₂ : Sk = L₂
⊢ ReflTransGen
    (fun a b ↦
      (match a with
        | { l := none, var := var, stk := stk } => none
        | { l := some l, var := v, stk := S } => some (TM2.stepAux (tr l) v S)) =
        some b)
    { l := some q, var := some a, stk := update S k Sk } { l := some q, var := o, stk := update S k L₂ }

Tactic:
e₁,

Goal state after:
case nil.cons.true
p : Γ' → Bool
k : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
s : Option Γ'
S : K' → List Γ'
a : Γ'
Sk : List Γ'
e₁ : some a = o
e₂ : Sk = L₂
⊢ ReflTransGen
    (fun a b ↦
      (match a with
        | { l := none, var := var, stk := stk } => none
        | { l := some l, var := v, stk := S } => some (TM2.stepAux (tr l) v S)) =
        some b)
    { l := some q, var := o, stk := update S k Sk } { l := some q, var := o, stk := update S k L₂ }
Module: Mathlib.Computability.TuringMachine.ToPartrec

Goal state before:
pp: case cons.nil
p : Γ' → Bool
k : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.clear p k q), var := s, stk := S }
        { l := some q, var := o, stk := update S k L₂ }
s : Option Γ'
S : K' → List Γ'
e : splitAtPred p (S k) = (a :: L₁, o, L₂)
e₁ : S k = []
⊢ TransGen
    (fun a b ↦
      (match a with
        | { l := none, var := var, stk := stk } => none
        | { l := some l, var := v, stk := S } => some (TM2.stepAux (tr l) v S)) =
        some b)
    (bif
        match [].head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := [].head?, stk := update S k [].tail }
    else { l := some (Λ'.clear p k q), var := [].head?, stk := update S k [].tail })
    { l := some q, var := o, stk := update S k L₂ }

Tactic:
e₁,

Goal state after:
case cons.nil
p : Γ' → Bool
k : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.clear p k q), var := s, stk := S }
        { l := some q, var := o, stk := update S k L₂ }
s : Option Γ'
S : K' → List Γ'
e : splitAtPred p [] = (a :: L₁, o, L₂)
e₁ : S k = []
⊢ TransGen
    (fun a b ↦
      (match a with
        | { l := none, var := var, stk := stk } => none
        | { l := some l, var := v, stk := S } => some (TM2.stepAux (tr l) v S)) =
        some b)
    (bif
        match [].head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := [].head?, stk := update S k [].tail }
    else { l := some (Λ'.clear p k q), var := [].head?, stk := update S k [].tail })
    { l := some q, var := o, stk := update S k L₂ }
Module: Mathlib.Computability.TuringMachine.ToPartrec

Goal state before:
pp: case cons.cons
p : Γ' → Bool
k : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.clear p k q), var := s, stk := S }
        { l := some q, var := o, stk := update S k L₂ }
s : Option Γ'
S : K' → List Γ'
e : splitAtPred p (S k) = (a :: L₁, o, L₂)
a' : Γ'
Sk : List Γ'
e₁ : S k = a' :: Sk
⊢ TransGen
    (fun a b ↦
      (match a with
        | { l := none, var := var, stk := stk } => none
        | { l := some l, var := v, stk := S } => some (TM2.stepAux (tr l) v S)) =
        some b)
    (bif
        match (a' :: Sk).head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := (a' :: Sk).head?, stk := update S k (a' :: Sk).tail }
    else { l := some (Λ'.clear p k q), var := (a' :: Sk).head?, stk := update S k (a' :: Sk).tail })
    { l := some q, var := o, stk := update S k L₂ }

Tactic:
e₁,

Goal state after:
case cons.cons
p : Γ' → Bool
k : K'
q : Λ'
o : Option Γ'
L₂ : List Γ'
a : Γ'
L₁ : List Γ'
IH :
  ∀ {s : Option Γ'} {S : K' → List Γ'},
    splitAtPred p (S k) = (L₁, o, L₂) →
      Reaches₁ (TM2.step tr) { l := some (Λ'.clear p k q), var := s, stk := S }
        { l := some q, var := o, stk := update S k L₂ }
s : Option Γ'
S : K' → List Γ'
a' : Γ'
Sk : List Γ'
e : splitAtPred p (a' :: Sk) = (a :: L₁, o, L₂)
e₁ : S k = a' :: Sk
⊢ TransGen
    (fun a b ↦
      (match a with
        | { l := none, var := var, stk := stk } => none
        | { l := some l, var := v, stk := S } => some (TM2.stepAux (tr l) v S)) =
        some b)
    (bif
        match (a' :: Sk).head?, true, p with
        | some x, x_1, f => f x
        | none, y, x => y then
      { l := some q, var := (a' :: Sk).head?, stk := update S k (a' :: Sk).tail }
    else { l := some (Λ'.clear p k q), var := (a' :: Sk).head?, stk := update S k (a' :: Sk).tail })
    { l := some q, var := o, stk := update S k L₂ }
Module: Mathlib.Topology.Separation.Profinite

Goal state before:
pp: case h_option.refine_5.some.none
X : Type u_4
I✝ : Type u_5
inst✝⁵ : TopologicalSpace X
inst✝⁴ : CompactSpace X
inst✝³ : T2Space X
inst✝² : TotallyDisconnectedSpace X
inst✝¹ : Finite I✝
I : Type u_5
inst✝ : Fintype I
IH :
  ∀ {Z D : I → Set X},
    (∀ (i : I), IsClosed[inst✝⁵] (Z i)) →
      (∀ (i : I), IsClopen (D i)) →
        (∀ (i : I), Z i ⊆ D i) →
          univ.PairwiseDisjoint Z →
            ∃ C,
              (∀ (i : I), IsClopen (C i)) ∧
                (∀ (i : I), Z i ⊆ C i) ∧ (∀ (i : I), C i ⊆ D i) ∧ ⋃ i, D i ⊆ ⋃ i, C i ∧ univ.PairwiseDisjoint C
Z D : Option I → Set X
Z_closed : ∀ (i : Option I), IsClosed[inst✝⁵] (Z i)
D_clopen : ∀ (i : Option I), IsClopen (D i)
Z_subset_D : ∀ (i : Option I), Z i ⊆ D i
Z_disj : univ.PairwiseDisjoint Z
Z' : I → Set X := fun i ↦ Z (some i)
Z'_closed : ∀ (i : I), IsClosed[inst✝⁵] (Z (some i))
Z'_disj : univ.PairwiseDisjoint (Z ∘ some)
U : Set X := D none \ ⋃ i, Z (some i)
U_open : IsOpen[inst✝⁵] U
Z0_subset_U : Z none ⊆ U
V : Set X
V_clopen : IsClopen V
Z0_subset_V : Z none ⊆ V
V_subset_U : V ⊆ U
V_subset_D0 : V ⊆ D none
D' : I → Set X := fun i ↦ D (some i) \ V
D'_clopen : ∀ (i : I), IsClopen (D' i)
Z'_subset_D' : ∀ (i : I), Z' i ⊆ D' i
C' : I → Set X
C'_clopen : ∀ (i : I), IsClopen (C' i)
Z'_subset_C' : ∀ (i : I), Z (some i) ⊆ C' i
C'_subset_D' : ∀ (i : I), C' i ⊆ D' i
C'_cover_D' : ⋃ i, D' i ⊆ ⋃ i, C' i
C'_disj : univ.PairwiseDisjoint C'
C0 : Set X := D none \ ⋃ i, C' i
this✝ : IsClopen C0
this : Z none ⊆ C0
C : Option I → Set X := fun i ↦ Option.casesOn i C0 C'
i : I
a✝¹ : some i ∈ univ
a✝ : none ∈ univ
⊢ (C (some i) ∩ C none).Nonempty → some i = none

Tactic:
simpa [C, C0, Set.not_nonempty_iff_eq_empty, ← Set.disjoint_iff_inter_eq_empty] using
          Disjoint.mono_left (subset_iUnion C' i) disjoint_sdiff_right

Goal state after:
Module: Mathlib.Computability.TuringMachine.ToPartrec

Goal state before:
pp: q₁ q₂ : Λ'
c d : List Γ'
v : List ℕ
n : ℕ
m : PosNum
IH :
  ∀ (s : Option Γ') (l₁ : List Γ'),
    ∃ l₁' l₂' s',
      l₁.reverseAux (trPosNum m) = l₁'.reverseAux l₂' ∧
        Reaches₁ (TM2.step tr)
          { l := some (q₁.pred q₂), var := s, stk := elim (trPosNum m.succ ++ Γ'.cons :: trList v) l₁ c d }
          { l := some (unrev q₂), var := s', stk := elim (l₂' ++ Γ'.cons :: trList v) l₁' c d }
s : Option Γ'
l₁ : List Γ'
⊢ ∃ a l, trPosNum m = a :: l ∧ natEnd a = false

Tactic:
cases m <;> refine ⟨_, _, rfl, rfl⟩

Goal state after:
Module: Mathlib.Topology.DiscreteQuotient

Goal state before:
pp: α : Type u_1
X : Type u_2
Y : Type u_3
Z : Type u_4
inst✝² : TopologicalSpace X
inst✝¹ : TopologicalSpace Y
inst✝ : TopologicalSpace Z
S : DiscreteQuotient X
x : X
⊢ IsOpen[inst✝²] (ofPred (S.toSetoid x))

Tactic:
exact S.isOpen_setOfPred_rel _

Goal state after: