mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Testing.Plausible.Functions

Goal state before:
pp: case cons.succ.cons.cons
α : Type u
inst✝ : DecidableEq α
x y x' : α
xs : List α
xs_ih :
  ∀ {ys : List α},
    xs.Nodup → xs.length = ys.length → ∀ (i : ℕ), xs[i]? = some x → (applyId (xs.zip ys) x = y ↔ ys[i]? = some y)
n✝ : ℕ
h₂ : xs[n✝]? = some x
head✝ : α
tail✝ : List α
h₁✝ : (x' :: xs).length = (head✝ :: tail✝).length
h₁ : List.Pairwise (fun x1 x2 ↦ x1 ≠ x2) xs
h₀ : ∀ a' ∈ xs, x' ≠ a'
⊢ applyId (xs.zip tail✝) x = y ↔ tail✝[n✝]? = some y

Tactic:
apply xs_ih

Goal state after:
case cons.succ.cons.cons.h₀
α : Type u
inst✝ : DecidableEq α
x y x' : α
xs : List α
xs_ih :
  ∀ {ys : List α},
    xs.Nodup → xs.length = ys.length → ∀ (i : ℕ), xs[i]? = some x → (applyId (xs.zip ys) x = y ↔ ys[i]? = some y)
n✝ : ℕ
h₂ : xs[n✝]? = some x
head✝ : α
tail✝ : List α
h₁✝ : (x' :: xs).length = (head✝ :: tail✝).length
h₁ : List.Pairwise (fun x1 x2 ↦ x1 ≠ x2) xs
h₀ : ∀ a' ∈ xs, x' ≠ a'
⊢ xs.Nodup

case cons.succ.cons.cons.h₁
α : Type u
inst✝ : DecidableEq α
x y x' : α
xs : List α
xs_ih :
  ∀ {ys : List α},
    xs.Nodup → xs.length = ys.length → ∀ (i : ℕ), xs[i]? = some x → (applyId (xs.zip ys) x = y ↔ ys[i]? = some y)
n✝ : ℕ
h₂ : xs[n✝]? = some x
head✝ : α
tail✝ : List α
h₁✝ : (x' :: xs).length = (head✝ :: tail✝).length
h₁ : List.Pairwise (fun x1 x2 ↦ x1 ≠ x2) xs
h₀ : ∀ a' ∈ xs, x' ≠ a'
⊢ xs.length = tail✝.length

case cons.succ.cons.cons.h₂
α : Type u
inst✝ : DecidableEq α
x y x' : α
xs : List α
xs_ih :
  ∀ {ys : List α},
    xs.Nodup → xs.length = ys.length → ∀ (i : ℕ), xs[i]? = some x → (applyId (xs.zip ys) x = y ↔ ys[i]? = some y)
n✝ : ℕ
h₂ : xs[n✝]? = some x
head✝ : α
tail✝ : List α
h₁✝ : (x' :: xs).length = (head✝ :: tail✝).length
h₁ : List.Pairwise (fun x1 x2 ↦ x1 ≠ x2) xs
h₀ : ∀ a' ∈ xs, x' ≠ a'
⊢ xs[n✝]? = some x
Module: Mathlib.Testing.Plausible.Functions

Goal state before:
pp: case none
α : Type u
inst✝ : DecidableEq α
xs ys : List α
h₀ : xs.Nodup
h₁ : xs ~ ys
x : α
h₃ : dlookup x (map Prod.toSigma (xs.zip ys)) = none
⊢ none.getD x ∈ ys ↔ x ∈ xs

Tactic:
dsimp [Option.getD]
    rw [h₁.mem_iff]

Goal state after:
Module: Mathlib.Testing.Plausible.Functions

Goal state before:
pp: α : Type u
inst✝ : DecidableEq α
xs : List ((_ : α) × α)
xs₀ : List α
h₀ : map Sigma.fst xs = xs₀
xs₁ : List α
h₁ : map Sigma.snd xs = xs₁
hxs : xs = List.toFinmap' (xs₀.zip xs₁)
⊢ ∀ (hperm : map Sigma.fst xs ~ map Sigma.snd xs) (hnodup : (map Sigma.snd xs).Nodup),
    Injective (mapToSelf xs hperm hnodup).apply

Tactic:
rw [hxs]

Goal state after:
α : Type u
inst✝ : DecidableEq α
xs : List ((_ : α) × α)
xs₀ : List α
h₀ : map Sigma.fst xs = xs₀
xs₁ : List α
h₁ : map Sigma.snd xs = xs₁
hxs : xs = List.toFinmap' (xs₀.zip xs₁)
⊢ ∀ (hperm : map Sigma.fst (List.toFinmap' (xs₀.zip xs₁)) ~ map Sigma.snd (List.toFinmap' (xs₀.zip xs₁)))
    (hnodup : (map Sigma.snd (List.toFinmap' (xs₀.zip xs₁))).Nodup),
    Injective (mapToSelf (List.toFinmap' (xs₀.zip xs₁)) hperm hnodup).apply
Module: Mathlib.Topology.Algebra.Group.CompactOpen

Goal state before:
pp: X : Type u_7
Y : Type u_8
inst✝⁸ : TopologicalSpace X
inst✝⁷ : Group X
inst✝⁶ : IsTopologicalGroup X
inst✝⁵ : UniformSpace Y
inst✝⁴ : CommGroup Y
inst✝³ : IsUniformGroup Y
inst✝² : T0Space Y
inst✝¹ : CompactSpace Y
inst✝ : LocallyCompactSpace X
V : ℕ → Set Y
hV : ∀ {n : ℕ} {x : Y}, x ∈ V n → x * x ∈ V n → x ∈ V (n + 1)
hVo : (𝓝 1).HasBasis (fun x ↦ True) V
U0 : Set X
hU0c : IsCompact U0
hU0o : U0 ∈ 𝓝 1
U_aux : ℕ → ↑{S | S ∈ 𝓝 1} :=
  fun t ↦
    Nat.rec ⟨U0, hU0o⟩
      (fun x S ↦
        let h := ⋯;
        ⟨Classical.choose h, ⋯⟩)
      t
U : ℕ → Set X := fun n ↦ ↑(U_aux n)
hU1 : ∀ (n : ℕ), U n ∈ 𝓝 1
hU2 : ∀ (n : ℕ), U (n + 1) * U (n + 1) ⊆ U n
hU3 : ∀ (n : ℕ), U (n + 1) ⊆ U n
hU4 : ∀ (f : X →* Y), Set.MapsTo (⇑f) (U 0) (V 0) → ∀ (n : ℕ), Set.MapsTo (⇑f) (U n) (V n)
n : ℕ
x✝¹ : True
x : X
hx : x ∈ U n
x✝ : ↑{f | Set.MapsTo (⇑f) (U 0) (V 0)}
f : X →* Y
hf : f ∈ {f | Set.MapsTo (⇑f) (U 0) (V 0)}
⊢ (↑⟨f, hf⟩ 1, ↑⟨f, hf⟩ x) ∈ {x | x.2 / x.1 ∈ V n}

Tactic:
Set.mem_ofPred_eq,

Goal state after:
X : Type u_7
Y : Type u_8
inst✝⁸ : TopologicalSpace X
inst✝⁷ : Group X
inst✝⁶ : IsTopologicalGroup X
inst✝⁵ : UniformSpace Y
inst✝⁴ : CommGroup Y
inst✝³ : IsUniformGroup Y
inst✝² : T0Space Y
inst✝¹ : CompactSpace Y
inst✝ : LocallyCompactSpace X
V : ℕ → Set Y
hV : ∀ {n : ℕ} {x : Y}, x ∈ V n → x * x ∈ V n → x ∈ V (n + 1)
hVo : (𝓝 1).HasBasis (fun x ↦ True) V
U0 : Set X
hU0c : IsCompact U0
hU0o : U0 ∈ 𝓝 1
U_aux : ℕ → ↑{S | S ∈ 𝓝 1} :=
  fun t ↦
    Nat.rec ⟨U0, hU0o⟩
      (fun x S ↦
        let h := ⋯;
        ⟨Classical.choose h, ⋯⟩)
      t
U : ℕ → Set X := fun n ↦ ↑(U_aux n)
hU1 : ∀ (n : ℕ), U n ∈ 𝓝 1
hU2 : ∀ (n : ℕ), U (n + 1) * U (n + 1) ⊆ U n
hU3 : ∀ (n : ℕ), U (n + 1) ⊆ U n
hU4 : ∀ (f : X →* Y), Set.MapsTo (⇑f) (U 0) (V 0) → ∀ (n : ℕ), Set.MapsTo (⇑f) (U n) (V n)
n : ℕ
x✝¹ : True
x : X
hx : x ∈ U n
x✝ : ↑{f | Set.MapsTo (⇑f) (U 0) (V 0)}
f : X →* Y
hf : f ∈ {f | Set.MapsTo (⇑f) (U 0) (V 0)}
⊢ (↑⟨f, hf⟩ 1, ↑⟨f, hf⟩ x).2 / (↑⟨f, hf⟩ 1, ↑⟨f, hf⟩ x).1 ∈ V n
Module: Mathlib.Topology.Algebra.Group.CompactOpen

Goal state before:
pp: X : Type u_7
Y : Type u_8
inst✝⁸ : TopologicalSpace X
inst✝⁷ : Group X
inst✝⁶ : IsTopologicalGroup X
inst✝⁵ : UniformSpace Y
inst✝⁴ : CommGroup Y
inst✝³ : IsUniformGroup Y
inst✝² : T0Space Y
inst✝¹ : CompactSpace Y
inst✝ : LocallyCompactSpace X
V : ℕ → Set Y
hV : ∀ {n : ℕ} {x : Y}, x ∈ V n → x * x ∈ V n → x ∈ V (n + 1)
hVo : (𝓝 1).HasBasis (fun x ↦ True) V
⊢ LocallyCompactSpace (X →ₜ* Y)

Tactic:
by
  obtain ⟨U0, hU0c, hU0o⟩ := exists_compact_mem_nhds (1 : X)
  let U_aux : ℕ → {S : Set X | S ∈ nhds 1} :=
    Nat.rec ⟨U0, hU0o⟩ <| fun _ S ↦ let h := exists_closed_nhds_one_inv_eq_mul_subset S.2
      ⟨Classical.choose h, (Classical.choose_spec h).1⟩
  let U : ℕ → Set X := fun n ↦ (U_aux n).1
  have hU1 : ∀ n, U n ∈ nhds 1 := fun n ↦ (U_aux n).2
  have hU2 : ∀ n, U (n + 1) * U (n + 1) ⊆ U n :=
    fun n ↦ (Classical.choose_spec (exists_closed_nhds_one_inv_eq_mul_subset (U_aux n).2)).2.2.2
  have hU3 : ∀ n, U (n + 1) ⊆ U n :=
    fun n x hx ↦ hU2 n (mul_one x ▸ Set.mul_mem_mul hx (mem_of_mem_nhds (hU1 (n + 1))))
  have hU4 : ∀ f : X →* Y, Set.MapsTo f (U 0) (V 0) → ∀ n, Set.MapsTo f (U n) (V n) := by
    intro f hf n
    induction n with
    | zero => exact hf
    | succ n ih =>
      exact fun x hx ↦ hV (ih (hU3 n hx)) (map_mul f x x ▸ ih (hU2 n (Set.mul_mem_mul hx hx)))
  apply locallyCompactSpace_of_equicontinuousAt (U 0) (V 0) hU0c (hVo.mem_of_mem trivial)
  rw [hVo.uniformity_of_nhds_one.equicontinuousAt_iff_right]
  refine fun n _ ↦ Filter.eventually_iff_exists_mem.mpr ⟨U n, hU1 n, fun x hx ⟨f, hf⟩ ↦ ?_⟩
  rw [Set.mem_ofPred_eq, map_one, div_one]
  exact hU4 f hf n hx

Goal state after:
Module: Mathlib.Topology.Algebra.Nonarchimedean.TotallyDisconnected

Goal state before:
pp: case h
G : Type u_1
inst✝³ : TopologicalSpace G
inst✝² : Group G
inst✝¹ : NonarchimedeanGroup G
inst✝ : T2Space G
a b : G
h : a ≠ b
u v : Set G
left✝ : IsOpen u
open_v : IsOpen v
mem_u : a⁻¹ * b ∈ u
mem_v : 1 ∈ v
dis : Disjoint u v
V : OpenSubgroup G
hV : ↑V ⊆ v
x : Set G
mem_aV : x ⊆ a • ↑V
mem_bV : x ⊆ b • ↑V
⊢ x = ∅

Tactic:
by_contra! ⟨s, hs⟩

Goal state after:
case h
G : Type u_1
inst✝³ : TopologicalSpace G
inst✝² : Group G
inst✝¹ : NonarchimedeanGroup G
inst✝ : T2Space G
a b : G
h : a ≠ b
u v : Set G
left✝ : IsOpen u
open_v : IsOpen v
mem_u : a⁻¹ * b ∈ u
mem_v : 1 ∈ v
dis : Disjoint u v
V : OpenSubgroup G
hV : ↑V ⊆ v
x : Set G
mem_aV : x ⊆ a • ↑V
mem_bV : x ⊆ b • ↑V
s : G
hs : s ∈ x
⊢ False
Module: Mathlib.Topology.Algebra.PontryaginDual

Goal state before:
pp: A : Type u_1
B : Type u_2
C : Type u_3
G : Type u_4
H : Type u_5
inst✝¹² : Monoid A
inst✝¹¹ : Monoid B
inst✝¹⁰ : Monoid C
inst✝⁹ : CommGroup G
inst✝⁸ : Group H
inst✝⁷ : TopologicalSpace A
inst✝⁶ : TopologicalSpace B
inst✝⁵ : TopologicalSpace C
inst✝⁴ : TopologicalSpace G
inst✝³ : TopologicalSpace H
inst✝² : IsTopologicalGroup G
inst✝¹ : IsTopologicalGroup H
inst✝ : LocallyCompactSpace H
Vn : ℕ → Set Circle := fun n ↦ Circle.centeredArc (π / 2 ^ (n + 1))
⊢ LocallyCompactSpace (PontryaginDual H)

Tactic:
have hVn : ∀ n x, x ∈ Vn n ↔ |Complex.arg x| < π / 2 ^ (n + 1) :=
    fun n x ↦ Circle.mem_centeredArc (z := x)
      (div_le_self pi_nonneg (one_le_pow₀ one_le_two))

Goal state after:
A : Type u_1
B : Type u_2
C : Type u_3
G : Type u_4
H : Type u_5
inst✝¹² : Monoid A
inst✝¹¹ : Monoid B
inst✝¹⁰ : Monoid C
inst✝⁹ : CommGroup G
inst✝⁸ : Group H
inst✝⁷ : TopologicalSpace A
inst✝⁶ : TopologicalSpace B
inst✝⁵ : TopologicalSpace C
inst✝⁴ : TopologicalSpace G
inst✝³ : TopologicalSpace H
inst✝² : IsTopologicalGroup G
inst✝¹ : IsTopologicalGroup H
inst✝ : LocallyCompactSpace H
Vn : ℕ → Set Circle := fun n ↦ Circle.centeredArc (π / 2 ^ (n + 1))
hVn : ∀ (n : ℕ) (x : Circle), x ∈ Vn n ↔ |(↑x).arg| < π / 2 ^ (n + 1)
⊢ LocallyCompactSpace (PontryaginDual H)
Module: Mathlib.Topology.CWComplex.Classical.Subcomplex

Goal state before:
pp: X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
E : Subcomplex C
⊢ univ.PairwiseDisjoint fun ni ↦ ↑(map ni.fst ↑ni.snd) '' ball 0 1

Tactic:
intro ⟨n, i⟩

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
E : Subcomplex C
n : ℕ
i : ↑(E.I n)
⊢ ⟨n, i⟩ ∈ univ →
    ∀ ⦃y : (n : ℕ) × ↑(E.I n)⦄,
      y ∈ univ → ⟨n, i⟩ ≠ y → Function.onFun Disjoint (fun ni ↦ ↑(map ni.fst ↑ni.snd) '' ball 0 1) ⟨n, i⟩ y
Module: Mathlib.Topology.Category.Compactum

Goal state before:
pp: X : Compactum
A : Set X.A
F : Ultrafilter X.A
hF : F ∈ basic (cl A)
fsu : Type u_1 := Finset (Set (Ultrafilter X.A))
ssu : Type u_1 := Set (Set (Ultrafilter X.A))
ι : fsu → ssu := fun x ↦ ↑x
C0 : ssu := {Z | ∃ B ∈ F, X.str ⁻¹' B = Z}
AA : Set (Ultrafilter X.A) := {G | A ∈ G}
C1 : ssu := insert AA C0
C2 : Set (Set (Ultrafilter X.A)) := finiteInterClosure C1
claim1 : ∀ B ∈ C0, ∀ C ∈ C0, B ∩ C ∈ C0
claim2 : ∀ B ∈ C0, B.Nonempty
claim3 : ∀ B ∈ C0, (AA ∩ B).Nonempty
claim4 : FiniteInter (finiteInterClosure C1)
claim5 : FiniteInter C0
claim6 : ∀ P ∈ C2, P.Nonempty
T : fsu
hT : ι T ⊆ C1
⊢ (⋂₀ ι T).Nonempty

Tactic:
suffices ⋂₀ ι T ∈ C2 by exact claim6 _ this

Goal state after:
X : Compactum
A : Set X.A
F : Ultrafilter X.A
hF : F ∈ basic (cl A)
fsu : Type u_1 := Finset (Set (Ultrafilter X.A))
ssu : Type u_1 := Set (Set (Ultrafilter X.A))
ι : fsu → ssu := fun x ↦ ↑x
C0 : ssu := {Z | ∃ B ∈ F, X.str ⁻¹' B = Z}
AA : Set (Ultrafilter X.A) := {G | A ∈ G}
C1 : ssu := insert AA C0
C2 : Set (Set (Ultrafilter X.A)) := finiteInterClosure C1
claim1 : ∀ B ∈ C0, ∀ C ∈ C0, B ∩ C ∈ C0
claim2 : ∀ B ∈ C0, B.Nonempty
claim3 : ∀ B ∈ C0, (AA ∩ B).Nonempty
claim4 : FiniteInter (finiteInterClosure C1)
claim5 : FiniteInter C0
claim6 : ∀ P ∈ C2, P.Nonempty
T : fsu
hT : ι T ⊆ C1
⊢ ⋂₀ ι T ∈ C2
Module: Mathlib.Topology.Category.Compactum

Goal state before:
pp: X : Compactum
A : Set X.A
⊢ cl (cl A) ⊆ cl A

Tactic:
rintro _ ⟨F, hF, rfl⟩
  -- Notation to be used in this proof.
  let fsu := Finset (Set (Ultrafilter X))
  let ssu := Set (Set (Ultrafilter X))
  let ι : fsu → ssu := fun x ↦ ↑x
  let C0 : ssu := { Z | ∃ B ∈ F, X.str ⁻¹' B = Z }
  let AA := { G : Ultrafilter X | A ∈ G }
  let C1 := insert AA C0
  let C2 := finiteInterClosure C1
  -- C0 is closed under intersections.
  have claim1 : ∀ (B) (_ : B ∈ C0) (C) (_ : C ∈ C0), B ∩ C ∈ C0 := by
    rintro B ⟨Q, hQ, rfl⟩ C ⟨R, hR, rfl⟩
    use Q ∩ R
    simp only [and_true, Set.preimage_inter]
    exact inter_sets _ hQ hR
  -- All sets in C0 are nonempty.
  have claim2 : ∀ B ∈ C0, Set.Nonempty B := by
    rintro B ⟨Q, hQ, rfl⟩
    obtain ⟨q⟩ := Filter.nonempty_of_mem hQ
    use X.incl q
    simpa
  -- The intersection of AA with every set in C0 is nonempty.
  have claim3 : ∀ B ∈ C0, (AA ∩ B).Nonempty := by
    rintro B ⟨Q, hQ, rfl⟩
    have : (Q ∩ cl A).Nonempty := Filter.nonempty_of_mem (inter_mem hQ hF)
    rcases this with ⟨q, hq1, P, hq2, hq3⟩
    refine ⟨P, hq2, ?_⟩
    rw [← hq3] at hq1
    simpa
  -- Suffices to show that the intersection of any finite subcollection of C1 is nonempty.
  suffices ∀ T : fsu, ι T ⊆ C1 → (⋂₀ ι T).Nonempty by
    obtain ⟨G, h1⟩ := exists_ultrafilter_of_finite_inter_nonempty _ this
    use X.join G
    have : G.map X.str = F := Ultrafilter.coe_le_coe.1 fun S hS => h1 (Or.inr ⟨S, hS, rfl⟩)
    rw [join_distrib, this]
    exact ⟨h1 (Or.inl rfl), rfl⟩
  -- C2 is closed under finite intersections (by construction!).
  have claim4 := finiteInterClosure_finiteInter C1
  -- C0 is closed under finite intersections by claim1.
  have claim5 : FiniteInter C0 := ⟨⟨_, univ_mem, Set.preimage_univ⟩, claim1⟩
  -- Every element of C2 is nonempty.
  have claim6 : ∀ P ∈ C2, (P : Set (Ultrafilter X)).Nonempty := by
    suffices ∀ P ∈ C2, P ∈ C0 ∨ ∃ Q ∈ C0, P = AA ∩ Q by
      intro P hP
      rcases this P hP with h | h
      · exact claim2 _ h
      · rcases h with ⟨Q, hQ, rfl⟩
        exact claim3 _ hQ
    intro P hP
    exact claim5.finiteInterClosure_insert _ hP
  intro T hT
  -- Suffices to show that the intersection of the T's is contained in C2.
  suffices ⋂₀ ι T ∈ C2 by exact claim6 _ this
  -- Finish
  apply claim4.finiteInter_mem T
  intro t ht
  exact finiteInterClosure.basic (@hT t ht)

Goal state after:
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: X : Type u_1
t : TopologicalSpace X
D C : Set X
inst✝ : RelCWComplex C D
x z : cell C 0
h : (fun x ↦ ↑(map 0 x) ![]) x = (fun x ↦ ↑(map 0 x) ![]) z
⊢ x = z

Tactic:
by_contra hne

Goal state after:
X : Type u_1
t : TopologicalSpace X
D C : Set X
inst✝ : RelCWComplex C D
x z : cell C 0
h : (fun x ↦ ↑(map 0 x) ![]) x = (fun x ↦ ↑(map 0 x) ![]) z
hne : ¬x = z
⊢ False
Module: Mathlib.Topology.Category.Profinite.Nobeling.Basic

Goal state before:
pp: I : Type u
C : Set (I → Bool)
J : I → Prop
inst✝ : (i : I) → Decidable (J i)
hh : ∀ (i : I), ∀ x ∈ C, x i ≠ false → J i
⊢ π C J = C

Tactic:
by
  ext x
  refine ⟨fun ⟨y, hy, h⟩ ↦ ?_, fun h ↦ ⟨x, h, ?_⟩⟩
  · rwa [← h, proj_eq_self]; exact (hh · y hy)
  · rw [proj_eq_self]; exact (hh · x h)

Goal state after:
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
⊢ Disjoint D (⋃ n, ⋃ j, openCell n j)

Tactic:
disjoint_iff_inter_eq_empty,

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
⊢ D ∩ ⋃ n, ⋃ j, openCell n j = ∅
Module: Mathlib.Topology.Category.Profinite.Nobeling.Span

Goal state before:
pp: case cons
I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
s : Finset I
inst✝ : WellFoundedLT I
x : ↑(π C fun x ↦ x ∈ s)
l : List I := s.sort fun x1 x2 ↦ x1 ≥ x2
a : I
as : List I
ih :
  List.IsChain (fun x1 x2 ↦ x1 > x2) as →
    (List.map (fun i ↦ if ↑x i = true then e (π C fun x ↦ x ∈ s) i else 1 - e (π C fun x ↦ x ∈ s) i) as).prod ∈
      Submodule.span ℤ (Products.eval (π C fun x ↦ x ∈ s) '' {m | ↑m ≤ as})
⊢ List.IsChain (fun x1 x2 ↦ x1 > x2) (a :: as) →
    (List.map (fun i ↦ if ↑x i = true then e (π C fun x ↦ x ∈ s) i else 1 - e (π C fun x ↦ x ∈ s) i) (a :: as)).prod ∈
      Submodule.span ℤ (Products.eval (π C fun x ↦ x ∈ s) '' {m | ↑m ≤ a :: as})

Tactic:
rw [List.map_cons, List.prod_cons]

Goal state after:
case cons
I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
s : Finset I
inst✝ : WellFoundedLT I
x : ↑(π C fun x ↦ x ∈ s)
l : List I := s.sort fun x1 x2 ↦ x1 ≥ x2
a : I
as : List I
ih :
  List.IsChain (fun x1 x2 ↦ x1 > x2) as →
    (List.map (fun i ↦ if ↑x i = true then e (π C fun x ↦ x ∈ s) i else 1 - e (π C fun x ↦ x ∈ s) i) as).prod ∈
      Submodule.span ℤ (Products.eval (π C fun x ↦ x ∈ s) '' {m | ↑m ≤ as})
⊢ List.IsChain (fun x1 x2 ↦ x1 > x2) (a :: as) →
    (if ↑x a = true then e (π C fun x ↦ x ∈ s) a else 1 - e (π C fun x ↦ x ∈ s) a) *
        (List.map (fun i ↦ if ↑x i = true then e (π C fun x ↦ x ∈ s) i else 1 - e (π C fun x ↦ x ∈ s) i) as).prod ∈
      Submodule.span ℤ (Products.eval (π C fun x ↦ x ∈ s) '' {m | ↑m ≤ a :: as})
Module: Mathlib.Topology.Category.Profinite.Nobeling.Basic

Goal state before:
pp: case inr
I : Type u
C : Set (I → Bool)
inst✝ : LinearOrder I
a : Products I
ha : Products.isGood C a
b : Products I
hb : Products.isGood C b
h : Products.eval C a = Products.eval C b
hne : ⟨a, ha⟩ ≠ ⟨b, hb⟩
h' : ⟨b, hb⟩ < ⟨a, ha⟩
⊢ False

Tactic:
apply ha; rw [h]; exact Submodule.subset_span ⟨b, h', rfl⟩

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

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝ : LinearOrder I
⊢ LinearIndependent ℤ (eval C) ↔ LinearIndependent ℤ fun (p : ↑(range C)) ↦ ↑p

Tactic:
rw [← @Set.rangeFactorization_eq _ _ (GoodProducts.eval C), ← equiv_toFun_eq_eval C]

Goal state after:
I : Type u
C : Set (I → Bool)
inst✝ : LinearOrder I
⊢ LinearIndependent ℤ (Subtype.val ∘ (equiv_range C).toFun) ↔ LinearIndependent ℤ fun (p : ↑(range C)) ↦ ↑p
Module: Mathlib.Topology.Category.Profinite.Nobeling.Span

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝ : LinearOrder I
hC : IsClosed C
f : LocallyConstant ↑C ℤ
⊢ ∃ s g, f = LocallyConstant.comap { toFun := ProjRestrict C fun x ↦ x ∈ s, continuous_toFun := ⋯ } g

Tactic:
obtain ⟨J, g, h⟩ := @Profinite.exists_locallyConstant (Finset I)ᵒᵖ _ _ _
    (spanCone hC.isCompact) ℤ
    (spanCone_isLimit hC.isCompact) f
  exact ⟨(Opposite.unop J), g, h⟩

Goal state after:
Module: Mathlib.Topology.Category.Profinite.Nobeling.ZeroLimit

Goal state before:
pp: I : Type u_1
inst✝ : LinearOrder I
⊢ ℤ ∙ eval {fun x ↦ false} nil = ⊤

Tactic:
eq_top_iff

Goal state after:
I : Type u_1
inst✝ : LinearOrder I
⊢ ⊤ ≤ ℤ ∙ eval {fun x ↦ false} nil
Module: Mathlib.Topology.Category.Profinite.Nobeling.ZeroLimit

Goal state before:
pp: case h
I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
x✝ : ↑(smaller C o)
a : LocallyConstant ↑C ℤ
b : LocallyConstant ↑(π C fun x ↦ ord I x < o) ℤ
hb : b ∈ range (π C fun x ↦ ord I x < o) ∧ (πs C o) b = a
⊢ (fun x ↦ ⟨(πs C o) ↑x, ⋯⟩) ⟨b, ⋯⟩ = ⟨a, ⋯⟩

Tactic:
simpa only [Subtype.mk.injEq] using hb.2

Goal state after:
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: case h.inr.inl
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
n : ℕ
i : cell C (n + 1)
J : (m : ℕ) → Finset (cell C m)
p : (m : ℕ) → m ≤ n → cell C m → (m : ℕ) → Finset (cell C m)
I : (m : ℕ) → Finset (cell C m) :=
  fun m ↦ J m ∪ (Finset.range n.succ).biUnion fun l ↦ (J l).biUnion fun y ↦ if h : l ≤ n then p l h y m else ∅
x : X
hx : x ∈ cellFrontier (n + 1) i
l : ℕ
hln : l < n.succ
j : cell C l
hj : j ∈ J l
hxj : x ∈ cellFrontier l j
hp : x ∈ D ∨ ∃ i, ∃ (_ : i < l), ∃ i_1, ∃ (_ : i_1 ∈ p l ⋯ j i), x ∈ openCell i i_1
⊢ x ∈ D ∨ ∃ i < n + 1, ∃ i_1 ∈ I i, x ∈ openCell i i_1

Tactic:
exists_prop

Goal state after:
case h.inr.inl
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
n : ℕ
i : cell C (n + 1)
J : (m : ℕ) → Finset (cell C m)
p : (m : ℕ) → m ≤ n → cell C m → (m : ℕ) → Finset (cell C m)
I : (m : ℕ) → Finset (cell C m) :=
  fun m ↦ J m ∪ (Finset.range n.succ).biUnion fun l ↦ (J l).biUnion fun y ↦ if h : l ≤ n then p l h y m else ∅
x : X
hx : x ∈ cellFrontier (n + 1) i
l : ℕ
hln : l < n.succ
j : cell C l
hj : j ∈ J l
hxj : x ∈ cellFrontier l j
hp : x ∈ D ∨ ∃ i < l, ∃ i_1 ∈ p l ⋯ j i, x ∈ openCell i i_1
⊢ x ∈ D ∨ ∃ i < n + 1, ∃ i_1 ∈ I i, x ∈ openCell i i_1
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
n m : ℕ∞
h : m ≤ n
x : X
xmem : ∃ i, ∃ (_ : ↑i < m), ∃ i_1, x ∈ closedCell i i_1
⊢ ∃ i, ∃ (_ : ↑i < n), ∃ i_1, x ∈ closedCell i i_1

Tactic:
exists_prop

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
n m : ℕ∞
h : m ≤ n
x : X
xmem : ∃ i, ↑i < m ∧ ∃ i_1, x ∈ closedCell i i_1
⊢ ∃ i, ↑i < n ∧ ∃ i_1, x ∈ closedCell i i_1
Module: Mathlib.Topology.Category.Profinite.Nobeling.Successor

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝² : LinearOrder I
inst✝¹ : WellFoundedLT I
o : Ordinal.{u}
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
inst✝ : Inhabited I
l : Products I
hl : ↑l ≠ []
hlh : (↑l).head! = term I ho
hlc : List.IsChain (fun x1 x2 ↦ x1 > x2) (term I ho :: ↑l.Tail)
x : ↑(C' C ho)
⊢ (e C (term I ho)) (CC'₁ C hsC ho x) * (eval C l.Tail) (CC'₁ C hsC ho x) -
      (e C (term I ho)) (CC'₀ C ho x) * (eval C l.Tail) (CC'₀ C ho x) =
    (eval (C' C ho) (Tail ⟨term I ho :: ↑l.Tail, hlc⟩)) x

Tactic:
CC'₁,

Goal state after:
I : Type u
C : Set (I → Bool)
inst✝² : LinearOrder I
inst✝¹ : WellFoundedLT I
o : Ordinal.{u}
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
inst✝ : Inhabited I
l : Products I
hl : ↑l ≠ []
hlh : (↑l).head! = term I ho
hlc : List.IsChain (fun x1 x2 ↦ x1 > x2) (term I ho :: ↑l.Tail)
x : ↑(C' C ho)
⊢ (e C (term I ho)) ⟨SwapTrue o ↑x, ⋯⟩ * (eval C l.Tail) ⟨SwapTrue o ↑x, ⋯⟩ -
      (e C (term I ho)) (CC'₀ C ho x) * (eval C l.Tail) (CC'₀ C ho x) =
    (eval (C' C ho) (Tail ⟨term I ho :: ↑l.Tail, hlc⟩)) x
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
n : ℕ
j : cell C n
x : X
xmem : x ∈ closedCell n j
⊢ ∃ i, ∃ (_ : ↑i < ↑n + 1), ∃ i_1, x ∈ closedCell i i_1

Tactic:
exists_prop

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
n : ℕ
j : cell C n
x : X
xmem : x ∈ closedCell n j
⊢ ∃ i, ↑i < ↑n + 1 ∧ ∃ i_1, x ∈ closedCell i i_1
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: case coe
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
x : X
m a✝ : ℕ
⊢ m < a✝ + 1 ↔ ↑m ≤ ↑a✝

Tactic:
Nat.cast_le,

Goal state after:
case coe
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
x : X
m a✝ : ℕ
⊢ m < a✝ + 1 ↔ m ≤ a✝
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
⊢ Disjoint (interior D) (⋃ n, ⋃ j, closedCell n j)

Tactic:
disjoint_iff_inter_eq_empty,

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝¹ : T2Space X
inst✝ : RelCWComplex C D
⊢ interior D ∩ ⋃ n, ⋃ j, closedCell n j = ∅
Module: Mathlib.Topology.Compactness.CompactSystem

Goal state before:
pp: α : Type u_1
S : Set (Set α)
h : ∀ (C : ℕ → Set α), (∀ (i : ℕ), C i ∈ S) → (∀ (n : ℕ), (⋂ k, ⋂ (_ : k < n), C k).Nonempty) → (⋂ i, C i).Nonempty
C : ℕ → Set α
hi : ∀ (i : ℕ), C i ∈ S
h' : ∀ (n : ℕ), dissipate C n ≠ ∅
⊢ ∀ (n : ℕ), ⋂ k, ⋂ (_ : k < n), C k ≠ ∅

Tactic:
refine fun n g ↦ h' n ?_

Goal state after:
α : Type u_1
S : Set (Set α)
h : ∀ (C : ℕ → Set α), (∀ (i : ℕ), C i ∈ S) → (∀ (n : ℕ), (⋂ k, ⋂ (_ : k < n), C k).Nonempty) → (⋂ i, C i).Nonempty
C : ℕ → Set α
hi : ∀ (i : ℕ), C i ∈ S
h' : ∀ (n : ℕ), dissipate C n ≠ ∅
n : ℕ
g : ⋂ k, ⋂ (_ : k < n), C k = ∅
⊢ dissipate C n = ∅
Module: Mathlib.Topology.Compactness.CompactSystem

Goal state before:
pp: case neg
α : Type u_1
S : Set (Set α)
hpi : IsPiSystem S
h : ∀ (C : ℕ → Set α), Directed (fun x1 x2 ↦ x1 ⊇ x2) C → (∀ (i : ℕ), C i ∈ S) → ⋂ i, C i = ∅ → ∃ n, C n = ∅
C : ℕ → Set α
h1 : ∀ (i : ℕ), C i ∈ insert ∅ S
h2 : ⋂ n, ⋂ m, ⋂ (_ : m ≤ n), C m = ∅
this : (∀ (n : ℕ), dissipate C n ∈ S ∨ dissipate C n = ∅) ∧ ⋂ n, dissipate C n = ∅
f : ∃ n, dissipate C n ∉ S
⊢ ∃ n, dissipate C n = ∅

Tactic:
· obtain ⟨n, hn⟩ := f
      exact ⟨n, by simpa [hn] using this.1 n⟩

Goal state after:
Module: Mathlib.Topology.Compactness.CompactSystem

Goal state before:
pp: case refine_1
α : Type u_1
S : Set (Set α)
hpi : IsPiSystem S
h1 : ∀ (C : ℕ → Set α), Directed (fun x1 x2 ↦ x1 ⊇ x2) C → (∀ (i : ℕ), C i ∈ S) → ⋂ i, C i = ∅ → ∃ n, C n = ∅
C : ℕ → Set α
h3 : Directed (fun x1 x2 ↦ x1 ⊇ x2) C
h4 : ∀ (i : ℕ), C i ∈ S
⊢ ⋂ i, C i = ∅ → ∃ n, C n = ∅

Tactic:
exact h1 C h3 h4

Goal state after: