mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Tactic.ComputeAsymptotics.Multiseries.Corecursion

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
F : β → Option (α × γ × β)
op : γ → Stream'.Seq α → Stream'.Seq α
h : FriendlyOperationClass op
T : (β →ᵤ Stream'.Seq α) → β →ᵤ Stream'.Seq α :=
  fun f b ↦
    match F b with
    | none => nil
    | some (a, c, b') => Seq.cons a (op c (f b'))
f g : β →ᵤ Stream'.Seq α
b : β
a : α
c : γ
b' : β
⊢ dist (op c (f b')) (op c (g b')) ≤ dist (f b') (g b')

Tactic:
by
          have := h.friend c
          rw [FriendlyOperation, lipschitzWith_iff_dist_le_mul] at this
          specialize this (f b') (g b')
          simpa using this

Goal state after:
Module: Mathlib.Tactic.ComputeAsymptotics.Multiseries.Basic

Goal state before:
pp: case cons
c : ℝ
basis_hd : ℝ → ℝ
basis_tl : List (ℝ → ℝ)
h_basis : WellFormedBasis (basis_hd :: basis_tl)
⊢ (const (basis_hd :: basis_tl) c).Approximates

Tactic:
simp only [const, Multiseries.const]
    apply (const_approximates h_basis.tail).cons _ (by simp)
    exact Majorized.const <| h_basis.tendsto_atTop (by simp)

Goal state after:
Module: Mathlib.Tactic.ComputeAsymptotics.Multiseries.Monomial.Basic

Goal state before:
pp: case nil
basis : Basis
h_basis : WellFormedBasis basis
h_length : [].length = List.length basis
h_firstIsPos : FirstNonzeroIsPos []
⊢ Tendsto (toFun [] basis) atTop atTop

Tactic:
simp at h_firstIsPos

Goal state after:
Module: Mathlib.SetTheory.Ordinal.Notation

Goal state before:
pp: case oadd.inl.none.inl.some.succ.refine_2
a : ONote
m : ℕ+
b : ONote
ihb : b = 0
e✝ : b.fundamentalSequence = Sum.inl none
a' : ONote
iha : a.repr = succ a'.repr ∧ (a.NF → a'.NF)
e : a.fundamentalSequence = Sum.inl (some a')
m' : ℕ
e' : m.natPred = m' + 1
this : 0 < ω ^ a'.repr
i : ℕ
H : (a.oadd (m' + 1).succPNat 0).NF
⊢ ω ^ a'.repr * ↑↑i.succPNat < ω ^ a.repr

Tactic:
iha.1,

Goal state after:
case oadd.inl.none.inl.some.succ.refine_2
a : ONote
m : ℕ+
b : ONote
ihb : b = 0
e✝ : b.fundamentalSequence = Sum.inl none
a' : ONote
iha : a.repr = succ a'.repr ∧ (a.NF → a'.NF)
e : a.fundamentalSequence = Sum.inl (some a')
m' : ℕ
e' : m.natPred = m' + 1
this : 0 < ω ^ a'.repr
i : ℕ
H : (a.oadd (m' + 1).succPNat 0).NF
⊢ ω ^ a'.repr * ↑↑i.succPNat < ω ^ succ a'.repr
Module: Mathlib.SetTheory.Ordinal.Notation

Goal state before:
pp: case oadd.inl.some.refine_2
a : ONote
m : ℕ+
b : ONote
iha : a.FundamentalSequenceProp a.fundamentalSequence
b' : ONote
ihb : b.repr = succ b'.repr ∧ (b.NF → b'.NF)
e : b.fundamentalSequence = Sum.inl (some b')
H : (a.oadd m b).NF
this : succ b'.repr < ω ^ a.repr
⊢ b'.repr < ω ^ a.repr

Tactic:
exact (lt_succ _).trans this

Goal state after:
Module: Mathlib.Tactic.NormNum.IsCoprime

Goal state before:
pp: x y : ℤ
d : ℕ
hd : x.gcd y = d
h : d.beq 1 = false
⊢ ¬IsCoprime x y

Tactic:
Int.isCoprime_iff_gcd_eq_one,

Goal state after:
x y : ℤ
d : ℕ
hd : x.gcd y = d
h : d.beq 1 = false
⊢ ¬x.gcd y = 1
Module: Mathlib.Topology.UniformSpace.Ascoli

Goal state before:
pp: ι : Type u_1
X : Type u_2
α : Type u_3
inst✝¹ : TopologicalSpace X
inst✝ : UniformSpace α
F : ι → X → α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn F K
⊢ UniformSpace.comap F (UniformOnFun.uniformSpace X α 𝔖) =
    ⨅ K ∈ 𝔖, UniformSpace.comap (K.domRestrict ∘ F) (UniformFun.uniformSpace (↑K) α)

Tactic:
UniformOnFun.uniformSpace,

Goal state after:
ι : Type u_1
X : Type u_2
α : Type u_3
inst✝¹ : TopologicalSpace X
inst✝ : UniformSpace α
F : ι → X → α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn F K
⊢ UniformSpace.comap F
      (⨅ s ∈ 𝔖,
        UniformSpace.comap (⇑UniformFun.ofFun ∘ s.domRestrict ∘ ⇑(UniformOnFun.toFun 𝔖))
          (UniformFun.uniformSpace (↑s) α)) =
    ⨅ K ∈ 𝔖, UniformSpace.comap (K.domRestrict ∘ F) (UniformFun.uniformSpace (↑K) α)
Module: Mathlib.Topology.UniformSpace.Ascoli

Goal state before:
pp: ι : Type u_1
X : Type u_2
α : Type u_3
inst✝¹ : TopologicalSpace X
inst✝ : UniformSpace α
F : ι → X → α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn F K
H : IsClosed[UniformOnFun.topologicalSpace X α 𝔖] (range (⇑(UniformOnFun.ofFun 𝔖) ∘ F))
⊢ IsClosed[Pi.topologicalSpace] (range ((⋃₀ 𝔖).domRestrict ∘ F))

Tactic:
by
  -- Do we have no equivalent of `nontriviality`?
  rcases isEmpty_or_nonempty α with _ | _
  · simp [isClosed_discrete]
  -- This follows from the previous lemmas and the characterization of the closure using filters.
  simp_rw [isClosed_iff_clusterPt, ← Filter.map_top, ← mapClusterPt_def,
    mapClusterPt_iff_ultrafilter, range_comp, Subtype.coe_injective.surjective_comp_right.forall,
    ← domRestrict_eq, ← EquicontinuousOn.tendsto_uniformOnFun_iff_pi' 𝔖_compact F_eqcont]
  exact fun f ⟨u, _, hu⟩ ↦ mem_image_of_mem _ <| H.mem_of_tendsto hu <|
    Eventually.of_forall mem_range_self

Goal state after:
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
n : ℕ
i : ↑(E.I n)
a✝ : ⟨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

Tactic:
⟨m, j⟩

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)
a✝ : ⟨n, i⟩ ∈ univ
m : ℕ
j : ↑(E.I m)
⊢ ⟨m, j⟩ ∈ univ → ⟨n, i⟩ ≠ ⟨m, j⟩ → Function.onFun Disjoint (fun ni ↦ ↑(map ni.fst ↑ni.snd) '' ball 0 1) ⟨n, i⟩ ⟨m, j⟩
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
n : ℕ
i : cell C n
⊢ ↑(map n i) 0 ∈ openCell n i

Tactic:
apply mem_image_of_mem

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
n : ℕ
i : cell C n
⊢ 0 ∈ ball 0 1
Module: Mathlib.Topology.Category.Profinite.Nobeling.Span

Goal state before:
pp: case false
I : Type u
C : Set (I → Bool)
inst✝ : LinearOrder I
s : Finset I
x y : ↑(π C fun x ↦ x ∈ s)
h : y ≠ x
a : I
ha : ↑y a = true
hx : ↑x a = false
⊢ 1 - 1 = 0

Tactic:
sub_self

Goal state after:
case false
I : Type u
C : Set (I → Bool)
inst✝ : LinearOrder I
s : Finset I
x y : ↑(π C fun x ↦ x ∈ s)
h : y ≠ x
a : I
ha : ↑y a = true
hx : ↑x a = false
⊢ 0 = 0
Module: Mathlib.Topology.CWComplex.Classical.Basic

Goal state before:
pp: case a.sr.hi
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
n : ℕ∞
m : ℕ
hm' : ∀ m_1 ≤ m, ↑m_1 < n → ∀ (j : cell C m_1), cellFrontier m_1 j ⊆ D ∪ ⋃ m, ⋃ (_ : ↑m < n), ⋃ j, openCell m j
hm : ↑(m + 1) < n
j : cell C (m + 1)
I : (m : ℕ) → Finset (cell C m)
hI : cellFrontier (m + 1) j ⊆ D ∪ ⋃ m_1, ⋃ (_ : m_1 < m + 1), ⋃ j ∈ I m_1, closedCell m_1 j
⊢ ⋃ m_1, ⋃ (_ : m_1 < m + 1), ⋃ j ∈ I m_1, closedCell m_1 j ⊆ D ∪ ⋃ m, ⋃ (_ : ↑m < n), ⋃ j, openCell m j

Tactic:
apply iUnion₂_subset fun l hl ↦ iUnion₂_subset fun i _ ↦ ?_

Goal state after:
X : Type u_1
t : TopologicalSpace X
C D : Set X
inst✝ : RelCWComplex C D
n : ℕ∞
m : ℕ
hm' : ∀ m_1 ≤ m, ↑m_1 < n → ∀ (j : cell C m_1), cellFrontier m_1 j ⊆ D ∪ ⋃ m, ⋃ (_ : ↑m < n), ⋃ j, openCell m j
hm : ↑(m + 1) < n
j : cell C (m + 1)
I : (m : ℕ) → Finset (cell C m)
hI : cellFrontier (m + 1) j ⊆ D ∪ ⋃ m_1, ⋃ (_ : m_1 < m + 1), ⋃ j ∈ I m_1, closedCell m_1 j
l : ℕ
hl : l < m + 1
i : cell C l
x✝ : i ∈ I l
⊢ closedCell l i ⊆ D ∪ ⋃ m, ⋃ (_ : ↑m < n), ⋃ j, openCell m j
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
hp : x ∈ D ∪ ⋃ m, ⋃ (_ : m < l), ⋃ j_1 ∈ p l ⋯ j m, openCell m j_1
hj : j ∈ J l
hxj : x ∈ cellFrontier l j
⊢ x ∈ D ∨ ∃ i < n + 1, ∃ i_1 ∈ I i, x ∈ openCell i i_1

Tactic:
simp_rw [mem_union, mem_iUnion, exists_prop] at hp

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: case hDA
X : Type u_1
t : TopologicalSpace X
C✝ D✝ : Set X
inst✝¹ : T2Space X
C D : Set X
inst✝ : RelCWComplex C D
E : Set X
I : (n : ℕ) → Set (cell C n)
closedCell_subset : ∀ (n : ℕ) (i : ↑(I n)), closedCell n ↑i ⊆ E
union : D ∪ ⋃ n, ⋃ j, openCell n ↑j = E
hEC : E ⊆ C
this : D ⊆ E
⊢ IsClosed[t] (E ∩ D)

Tactic:
rw [inter_eq_right.2 this]

Goal state after:
case hDA
X : Type u_1
t : TopologicalSpace X
C✝ D✝ : Set X
inst✝¹ : T2Space X
C D : Set X
inst✝ : RelCWComplex C D
E : Set X
I : (n : ℕ) → Set (cell C n)
closedCell_subset : ∀ (n : ℕ) (i : ↑(I n)), closedCell n ↑i ⊆ E
union : D ∪ ⋃ n, ⋃ j, openCell n ↑j = E
hEC : E ⊆ C
this : D ⊆ E
⊢ IsClosed[t] D
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
C D : Set X
inst✝ : RelCWComplex C D
E : Set X
I : (n : ℕ) → Set (cell C n)
closedCell_subset : ∀ (n : ℕ) (i : ↑(I n)), closedCell n ↑i ⊆ E
union : D ∪ ⋃ n, ⋃ j, openCell n ↑j = E
hEC : E ⊆ C
n : ℕ
x✝ : 0 < n
j : cell C n
h : j ∈ I n
this : closedCell n j ⊆ E
⊢ IsClosed[t] (E ∩ closedCell n j)

Tactic:
rw [inter_eq_right.2 this]

Goal state after:
X : Type u_1
t : TopologicalSpace X
C✝ D✝ : Set X
inst✝¹ : T2Space X
C D : Set X
inst✝ : RelCWComplex C D
E : Set X
I : (n : ℕ) → Set (cell C n)
closedCell_subset : ∀ (n : ℕ) (i : ↑(I n)), closedCell n ↑i ⊆ E
union : D ∪ ⋃ n, ⋃ j, openCell n ↑j = E
hEC : E ⊆ C
n : ℕ
x✝ : 0 < n
j : cell C n
h : j ∈ I n
this : closedCell n j ⊆ E
⊢ IsClosed[t] (closedCell n j)
Module: Mathlib.Topology.Category.Profinite.Nobeling.Successor

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
q : ↑(GoodProducts (π C fun x ↦ ord I x < o))
l : ↑(MaxProducts C ho)
this : Inhabited I
⊢ List.Lex (fun x1 x2 ↦ x1 < x2) ↑↑q ↑↑l

Tactic:
by_cases h : q.val.val = []

Goal state after:
case pos
I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
q : ↑(GoodProducts (π C fun x ↦ ord I x < o))
l : ↑(MaxProducts C ho)
this : Inhabited I
h : ↑↑q = []
⊢ List.Lex (fun x1 x2 ↦ x1 < x2) ↑↑q ↑↑l

case neg
I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
q : ↑(GoodProducts (π C fun x ↦ ord I x < o))
l : ↑(MaxProducts C ho)
this : Inhabited I
h : ¬↑↑q = []
⊢ List.Lex (fun x1 x2 ↦ x1 < x2) ↑↑q ↑↑l
Module: Mathlib.Topology.ContinuousMap.BoundedCompactlySupported

Goal state before:
pp: case neg
α : Type u_1
γ : Type u_2
inst✝¹ : TopologicalSpace α
inst✝ : NonUnitalNormedRing γ
c : Nonempty α
f : α →ᵇ γ
h : f ∈ C_cb(α, γ)
hs : ¬(tsupport ⇑f).Nonempty
⊢ ∃ x, ‖f x‖ = ‖f‖

Tactic:
· suffices f = 0 by simp [this]
    rwa [not_nonempty_iff_eq_empty, tsupport_eq_empty_iff, ← coe_zero, ← DFunLike.ext'_iff] at hs

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

Goal state before:
pp: ι : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : TopologicalSpace E
inst✝² : TopologicalSpace F
A✝ B : Set E
inst✝¹ : SequentialSpace E
inst✝ : CountablyCompactSpace E
x : ℕ → E
hx : ∀ (x_1 : E) (x_2 : ℕ → ℕ), StrictMono x_2 → ¬Tendsto (x ∘ x_2) atTop (𝓝 x_1)
A : Set E := ⋃ i, closure[inst✝³] {x i}
this : IsCountablyCompact A
a : E
ha : a ∈ A ∧ MapClusterPt a atTop x
⊢ ∃ k, ∀ n > k, a ∉ closure[inst✝³] {x n}

Tactic:
by_contra!

Goal state after:
ι : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : TopologicalSpace E
inst✝² : TopologicalSpace F
A✝ B : Set E
inst✝¹ : SequentialSpace E
inst✝ : CountablyCompactSpace E
x : ℕ → E
hx : ∀ (x_1 : E) (x_2 : ℕ → ℕ), StrictMono x_2 → ¬Tendsto (x ∘ x_2) atTop (𝓝 x_1)
A : Set E := ⋃ i, closure[inst✝³] {x i}
this✝ : IsCountablyCompact A
a : E
ha : a ∈ A ∧ MapClusterPt a atTop x
this : ∀ (k : ℕ), ∃ n > k, a ∈ closure[inst✝³] {x n}
⊢ False
Module: Mathlib.Topology.Homotopy.HSpaces

Goal state before:
pp: X : Type u
Y : Type v
inst✝³ : TopologicalSpace X
inst✝² : TopologicalSpace Y
inst✝¹ : HSpace X
inst✝ : HSpace Y
⊢ ({ toFun := fun p ↦ (hmul (p.1.1, p.2.1), hmul (p.1.2, p.2.2)), continuous_toFun := ⋯ }.comp
        ((const (X × Y) (e, e)).prodMk (ContinuousMap.id (X × Y)))).HomotopyRel
    (ContinuousMap.id (X × Y)) {(e, e)}

Tactic:
by
    let G : I × X × Y → X × Y := fun p => (HSpace.eHmul (p.1, p.2.1), HSpace.eHmul (p.1, p.2.2))
    have hG : Continuous G := by fun_prop
    use! ⟨G, hG⟩
    · rintro ⟨x, y⟩
      exact Prod.ext (HSpace.eHmul.1.2 x) (HSpace.eHmul.1.2 y)
    · rintro ⟨x, y⟩
      exact Prod.ext (HSpace.eHmul.1.3 x) (HSpace.eHmul.1.3 y)
    · rintro t ⟨x, y⟩ h
      replace h := Prod.mk_inj.mp h
      exact Prod.ext (HSpace.eHmul.2 t x h.1) (HSpace.eHmul.2 t y h.2)

Goal state after:
Module: Mathlib.Topology.Homotopy.HomotopyGroup

Goal state before:
pp: N : Type u_1
X : Type u_2
inst✝ : TopologicalSpace X
x✝¹ : X
M : Type ?u.15
x : X
e : M ≃ N
p : ↑(Ω^ M X x)
y : N → ↑I
x✝ : y ∈ Cube.boundary N
n : N
hn : y n = 0 ∨ y n = 1
⊢ ((↑p).comp { toFun := fun t m ↦ t (e m), continuous_toFun := ⋯ }) y = x

Tactic:
simpa using p.2 _ ⟨e.symm n, by simpa using hn⟩

Goal state after:
Module: Mathlib.Topology.Instances.CantorSet

Goal state before:
pp: case succ.refine_1
f : ℝ ≃ₜ ℝ := Homeomorph.mulLeft₀ (1 / 3) ⋯
g : ℝ ≃ₜ ℝ := (Homeomorph.addLeft 2).trans f
n : ℕ
ih : IsClosed (preCantorSet n)
⊢ IsClosed ((fun x ↦ x / 3) '' preCantorSet n)

pp: case succ.refine_2
f : ℝ ≃ₜ ℝ := Homeomorph.mulLeft₀ (1 / 3) ⋯
g : ℝ ≃ₜ ℝ := (Homeomorph.addLeft 2).trans f
n : ℕ
ih : IsClosed (preCantorSet n)
⊢ IsClosed ((fun x ↦ (2 + x) / 3) '' preCantorSet n)

Tactic:
· simpa [f, div_eq_inv_mul] using f.isClosedEmbedding.isClosed_iff_image_isClosed.mp ih

Goal state after:
case succ.refine_2
f : ℝ ≃ₜ ℝ := Homeomorph.mulLeft₀ (1 / 3) ⋯
g : ℝ ≃ₜ ℝ := (Homeomorph.addLeft 2).trans f
n : ℕ
ih : IsClosed (preCantorSet n)
⊢ IsClosed ((fun x ↦ (2 + x) / 3) '' preCantorSet n)
Module: Mathlib.Topology.List

Goal state before:
pp: case refine_2
α : Type u_1
inst✝ : TopologicalSpace α
l : List α
⊢ ∀ (a : α),
    Tendsto length (𝓝 l) (pure l.length) → Tendsto (fun p ↦ (p.1 :: p.2).length) (𝓝 a ×ˢ 𝓝 l) (pure (a :: l).length)

Tactic:
a

Goal state after:
case refine_2
α : Type u_1
inst✝ : TopologicalSpace α
l : List α
a : α
⊢ Tendsto length (𝓝 l) (pure l.length) → Tendsto (fun p ↦ (p.1 :: p.2).length) (𝓝 a ×ˢ 𝓝 l) (pure (a :: l).length)
Module: Mathlib.Topology.MetricSpace.CoveringNumbers

Goal state before:
pp: X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : ∀ i ⊆ A, IsSeparated (↑ε) i → i = ∅
⊢ A = ∅

Tactic:
by_contra!

Goal state after:
X : Type u_1
inst✝ : PseudoEMetricSpace X
A : Set X
ε : ℝ≥0
h : ∀ i ⊆ A, IsSeparated (↑ε) i → i = ∅
this : A.Nonempty
⊢ False
Module: Mathlib.Topology.MetricSpace.HausdorffAlexandroff

Goal state before:
pp: X : Type u_1
inst✝² : Nonempty X
inst✝¹ : MetricSpace X
inst✝ : CompactSpace X
this : TopologicalSpace.SeparableSpace X := TopologicalSpace.SecondCountableTopology.to_separableSpace
emb : X → ℕ → ↑unitInterval
h_emb : Topology.IsEmbedding emb
KH : Set (ℕ → ↑unitInterval) := Set.range emb
g : X ≃ₜ ↑KH := h_emb.toHomeomorph
KC : Set (ℕ → Bool) := cantorToHilbert ⁻¹' KH
⊢ ∃ f, Continuous f ∧ Function.Surjective f

Tactic:
have hKC_closed : IsClosed KC :=
    IsClosed.preimage cantorToHilbert_continuous (Topology.IsClosedEmbedding.isClosed_range
    <| Continuous.isClosedEmbedding (Topology.IsEmbedding.continuous h_emb) h_emb.injective)

Goal state after:
X : Type u_1
inst✝² : Nonempty X
inst✝¹ : MetricSpace X
inst✝ : CompactSpace X
this : TopologicalSpace.SeparableSpace X := TopologicalSpace.SecondCountableTopology.to_separableSpace
emb : X → ℕ → ↑unitInterval
h_emb : Topology.IsEmbedding emb
KH : Set (ℕ → ↑unitInterval) := Set.range emb
g : X ≃ₜ ↑KH := h_emb.toHomeomorph
KC : Set (ℕ → Bool) := cantorToHilbert ⁻¹' KH
hKC_closed : IsClosed KC
⊢ ∃ f, Continuous f ∧ Function.Surjective f
Module: Mathlib.Topology.MetricSpace.HolderNorm

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : PseudoEMetricSpace X
inst✝ : PseudoEMetricSpace Y
r : ℝ≥0
f : X → Y
h : ∃ i, ∃ (_ : HolderWith i r f), ↑i < ∞
C : ℝ≥0
hC : HolderWith C r f
h✝ : ↑C < ∞
⊢ MemHolder r f

Tactic:
exact ⟨C, hC⟩

Goal state after:
Module: Mathlib.Topology.MetricSpace.Infsep

Goal state before:
pp: α : Type u_1
inst✝ : EDist α
x y : α
⊢ ∀ (x_1 : α),
    x_1 = x ∨ x_1 = y →
      ∀ (y_1 : α), y_1 = x ∨ y_1 = y → x_1 ≠ y_1 → edist x y ≤ edist x_1 y_1 ∨ edist y x ≤ edist x_1 y_1

Tactic:
rintro a (rfl | rfl) b (rfl | rfl) hab <;> (try simp only [le_refl, true_or, or_true])

Goal state after:
case inl.inl
α : Type u_1
inst✝ : EDist α
y b : α
hab : b ≠ b
⊢ edist b y ≤ edist b b ∨ edist y b ≤ edist b b

case inr.inr
α : Type u_1
inst✝ : EDist α
x b : α
hab : b ≠ b
⊢ edist x b ≤ edist b b ∨ edist b x ≤ edist b b
Module: Mathlib.Topology.MetricSpace.HolderNorm

Goal state before:
pp: case neg
X : Type u_1
Y : Type u_2
inst✝¹ : MetricSpace X
inst✝ : NormedAddCommGroup Y
r : ℝ≥0
f g : X → Y
hfg : eHolderNorm r f = ∞ ∨ eHolderNorm r g = ∞
⊢ eHolderNorm r (f + g) ≤ eHolderNorm r f + eHolderNorm r g

Tactic:
obtain (h | h) := hfg

Goal state after:
case neg.inl
X : Type u_1
Y : Type u_2
inst✝¹ : MetricSpace X
inst✝ : NormedAddCommGroup Y
r : ℝ≥0
f g : X → Y
h : eHolderNorm r f = ∞
⊢ eHolderNorm r (f + g) ≤ eHolderNorm r f + eHolderNorm r g

case neg.inr
X : Type u_1
Y : Type u_2
inst✝¹ : MetricSpace X
inst✝ : NormedAddCommGroup Y
r : ℝ≥0
f g : X → Y
h : eHolderNorm r g = ∞
⊢ eHolderNorm r (f + g) ≤ eHolderNorm r f + eHolderNorm r g
Module: Mathlib.Topology.MetricSpace.Infsep

Goal state before:
pp: case pos
α : Type u_1
inst✝¹ : EMetricSpace α
s : Set α
inst✝ : Finite ↑s
val✝ : Fintype ↑s
hs : s.Nontrivial
x : α
_hx : x ∈ s
y : α
_hy : y ∈ s
hxy : x ≠ y
hxy' : s.einfsep = edist x y
⊢ 0 < s.einfsep

Tactic:
exact hxy'.symm ▸ edist_pos.2 hxy

Goal state after:
Module: Mathlib.Topology.Order.UpperLowerSetTopology

Goal state before:
pp: α : Type u_1
inst✝² : Preorder α
inst✝¹ : TopologicalSpace α
inst✝ : Topology.IsUpperSet α
s : Set α
⊢ IsLowerSet ↑(lowerClosure s)

Tactic:
exact LowerSet.lower (lowerClosure s)

Goal state after:
Module: Mathlib.Topology.Order.UpperLowerSetTopology

Goal state before:
pp: case mpr
α : Type u_1
β : Type u_2
inst✝⁵ : Preorder α
inst✝⁴ : Preorder β
inst✝³ : TopologicalSpace α
inst✝² : TopologicalSpace β
inst✝¹ : Topology.IsUpperSet α
inst✝ : Topology.IsUpperSet β
f : α → β
hf : Continuous[inst✝³, inst✝²] f
⊢ Monotone f

Tactic:
a

Goal state after:
case mpr
α : Type u_1
β : Type u_2
inst✝⁵ : Preorder α
inst✝⁴ : Preorder β
inst✝³ : TopologicalSpace α
inst✝² : TopologicalSpace β
inst✝¹ : Topology.IsUpperSet α
inst✝ : Topology.IsUpperSet β
f : α → β
hf : Continuous[inst✝³, inst✝²] f
a : α
⊢ ∀ ⦃b : α⦄, a ≤ b → f a ≤ f b
Module: Mathlib.Topology.Order.ScottTopology

Goal state before:
pp: α : Type u_1
s : Set α
D : Set (Set α)
inst✝¹ : Preorder α
t : TopologicalSpace α
inst✝ : IsScottHausdorff α D
hDL : IsLowerSet D
⊢ (∀ ⦃d : Set α⦄,
      d ∈ D → d.Nonempty → DirectedOn (fun x1 x2 ↦ x1 ≤ x2) d → ∀ ⦃a : α⦄, IsLUB d a → a ∈ s → ∃ b ∈ d, Ici b ∩ d ⊆ s) ↔
    DirSupInaccOn D s

Tactic:
dirSupInaccOn_iff_inter_subset hDL

Goal state after:
α : Type u_1
s : Set α
D : Set (Set α)
inst✝¹ : Preorder α
t : TopologicalSpace α
inst✝ : IsScottHausdorff α D
hDL : IsLowerSet D
⊢ (∀ ⦃d : Set α⦄,
      d ∈ D → d.Nonempty → DirectedOn (fun x1 x2 ↦ x1 ≤ x2) d → ∀ ⦃a : α⦄, IsLUB d a → a ∈ s → ∃ b ∈ d, Ici b ∩ d ⊆ s) ↔
    ∀ ⦃d : Set α⦄,
      d ∈ D → d.Nonempty → DirectedOn (fun x1 x2 ↦ x1 ≤ x2) d → ∀ ⦃a : α⦄, IsLUB d a → a ∈ s → ∃ b ∈ d, Ici b ∩ d ⊆ s
Module: Mathlib.Topology.Order.LowerUpperTopology

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝⁵ : CompleteLattice α
inst✝⁴ : CompleteLattice β
inst✝³ : TopologicalSpace α
inst✝² : IsLower α
inst✝¹ : TopologicalSpace β
inst✝ : IsLower β
f : sInfHom α β
b : β
⊢ ⇑f ⁻¹' Ici b = Ici (sInf (⇑f ⁻¹' Ici b))

Tactic:
refine Subset.antisymm (fun a => sInf_le) fun a ha => le_trans ?_ <|
    OrderHomClass.mono (f : α →o β) ha

Goal state after:
α : Type u_1
β : Type u_2
inst✝⁵ : CompleteLattice α
inst✝⁴ : CompleteLattice β
inst✝³ : TopologicalSpace α
inst✝² : IsLower α
inst✝¹ : TopologicalSpace β
inst✝ : IsLower β
f : sInfHom α β
b : β
a : α
ha : a ∈ Ici (sInf (⇑f ⁻¹' Ici b))
⊢ b ≤ ↑f (sInf (⇑f ⁻¹' Ici b))
Module: Mathlib.Topology.Order.LowerUpperTopology

Goal state before:
pp: α : Type u_1
inst✝¹ : Preorder α
inst✝ : TopologicalSpace α
⊢ IsUpper αᵒᵈ ↔ IsLower α

Tactic:
by
  constructor
  · apply OrderDual.instIsLower
  · apply OrderDual.instIsUpper

Goal state after:
Module: Mathlib.Topology.Order.HullKernel

Goal state before:
pp: case mpr
α : Type u_1
inst✝³ : SemilatticeInf α
T : Set α
inst✝² : OrderTop α
inst✝¹ : TopologicalSpace α
inst✝ : IsLower α
hT : ∀ p ∈ T, InfPrime p
R : Set ↑T
ha : ∃ a, a.Finite ∧ (Subtype.val ⁻¹' ↑(upperClosure a))ᶜ = R
⊢ ∃ a, (hull T a)ᶜ = R

Tactic:
obtain ⟨F, hF⟩ := ha

Goal state after:
case mpr
α : Type u_1
inst✝³ : SemilatticeInf α
T : Set α
inst✝² : OrderTop α
inst✝¹ : TopologicalSpace α
inst✝ : IsLower α
hT : ∀ p ∈ T, InfPrime p
R : Set ↑T
F : Set α
hF : F.Finite ∧ (Subtype.val ⁻¹' ↑(upperClosure F))ᶜ = R
⊢ ∃ a, (hull T a)ᶜ = R
Module: Mathlib.Topology.Partial

Goal state before:
pp: case mp
X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X →. Y
⊢ PContinuous f → ∀ {x : X} {y : Y}, y ∈ f x → PTendsto' f (𝓝 x) (𝓝 y)

Tactic:
intro h x y h'

Goal state after:
case mp
X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X →. Y
h : PContinuous f
x : X
y : Y
h' : y ∈ f x
⊢ PTendsto' f (𝓝 x) (𝓝 y)
Module: Mathlib.Topology.MetricSpace.GromovHausdorff

Goal state before:
pp: X : Type u
inst✝ : MetricSpace X
p q : NonemptyCompacts X
ha : Isometry Subtype.val
hb : Isometry Subtype.val
A : dist p q = hausdorffDist ↑p ↑q
I : ↑p = range Subtype.val
J : ↑q = range Subtype.val
⊢ dist p.toGHSpace q.toGHSpace ≤ dist p q

Tactic:
rw [A, I, J]

Goal state after:
X : Type u
inst✝ : MetricSpace X
p q : NonemptyCompacts X
ha : Isometry Subtype.val
hb : Isometry Subtype.val
A : dist p q = hausdorffDist ↑p ↑q
I : ↑p = range Subtype.val
J : ↑q = range Subtype.val
⊢ dist p.toGHSpace q.toGHSpace ≤ hausdorffDist (range Subtype.val) (range Subtype.val)
Module: Mathlib.Topology.Sets.BaseChangeNhds

Goal state before:
pp: α : Type u_1
inst✝¹ : TopologicalSpace α
K : Compacts α
inst✝ : T2Space α
L : ↑K.compactNhds
U : Opens α
h1 : ↑K ⊆ ↑U
h2 : ↑U ⊆ ↑↑L
h3 : closure ↑U ⊆ ↑↑L
⊢ ∃ j₂, K.openRcNhdsToCompactNhds j₂ ≤ L

Tactic:
exact ⟨⟨U, ⟨ IsCompact.of_isClosed_subset L.1.isCompact' isClosed_closure h3, h1⟩⟩, h3⟩

Goal state after: