mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Topology.Separation.GDelta

Goal state before:
pp: case inr
X : Type u_1
inst✝¹ : TopologicalSpace X
s t : Set X
inst✝ : NormalSpace X
st_dis : Disjoint s t
t_cl : IsClosed[inst✝¹] t
T : Set (Set X)
T_open : ∀ t ∈ T, IsOpen[inst✝¹] t
T_count : T.Countable
T_int : t = ⋂₀ T
T_nonempty : T.Nonempty
⊢ HasSeparatingCover s t

Tactic:
obtain ⟨g, g_surj⟩ := T_count.exists_surjective T_nonempty

Goal state after:
case inr
X : Type u_1
inst✝¹ : TopologicalSpace X
s t : Set X
inst✝ : NormalSpace X
st_dis : Disjoint s t
t_cl : IsClosed[inst✝¹] t
T : Set (Set X)
T_open : ∀ t ∈ T, IsOpen[inst✝¹] t
T_count : T.Countable
T_int : t = ⋂₀ T
T_nonempty : T.Nonempty
g : ℕ → ↑T
g_surj : Surjective g
⊢ HasSeparatingCover s t
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: α : Type u_1
M : Type u_2
inst✝² : Monoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
n : ℕ
⊢ Measurable fun x ↦ (x, n).1 ^ (x, n).2

Tactic:
induction n with
      | zero => simp only [pow_zero, ← Pi.one_def, measurable_one]
      | succ n ih =>
        simp only [pow_succ]
        exact ih.mul measurable_id

Goal state after:
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: α : Type u_3
m : MeasurableSpace α
G : Type u_4
inst✝² : InvolutiveInv G
inst✝¹ : MeasurableSpace G
inst✝ : MeasurableInv G
f : α → G
h : Measurable fun x ↦ (f x)⁻¹
⊢ Measurable f

Tactic:
simpa using

Goal state after:
α : Type u_3
m : MeasurableSpace α
G : Type u_4
inst✝² : InvolutiveInv G
inst✝¹ : MeasurableSpace G
inst✝ : MeasurableInv G
f : α → G
h : Measurable fun x ↦ (f x)⁻¹
⊢ Measurable f
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: α : Type u_3
m : MeasurableSpace α
μ : Measure α
G : Type u_4
inst✝² : InvolutiveInv G
inst✝¹ : MeasurableSpace G
inst✝ : MeasurableInv G
f : α → G
h : AEMeasurable (fun x ↦ (f x)⁻¹) μ
⊢ AEMeasurable f μ

Tactic:
simpa using

Goal state after:
α : Type u_3
m : MeasurableSpace α
μ : Measure α
G : Type u_4
inst✝² : InvolutiveInv G
inst✝¹ : MeasurableSpace G
inst✝ : MeasurableInv G
f : α → G
h : AEMeasurable (fun x ↦ (f x)⁻¹) μ
⊢ AEMeasurable f μ
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: α : Type u_1
inst✝² : MeasurableSpace α
inst✝¹ : Group α
inst✝ : MeasurableDiv α
⊢ Measurable Inv.inv

Tactic:
simpa using

Goal state after:
α : Type u_1
inst✝² : MeasurableSpace α
inst✝¹ : Group α
inst✝ : MeasurableDiv α
⊢ Measurable Inv.inv
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: α✝ : Type u_1
M : Type u_2
X : Type u_3
α : Type u_4
β : Type u_5
inst✝⁶ : MeasurableSpace X
inst✝⁵ : SMul M X
m : MeasurableSpace α
mβ : MeasurableSpace β
μ : Measure α
f : α → M
g : α → X
inst✝⁴ : MeasurableConstSMul M X
inst✝³ : SMul M α
inst✝² : SMul Mᵐᵒᵖ α
inst✝¹ : IsCentralScalar M α
inst✝ : MeasurableConstSMul M α
⊢ ∀ (c : Mᵐᵒᵖ), Measurable fun x ↦ c • x

Tactic:
simpa using

Goal state after:
α✝ : Type u_1
M : Type u_2
X : Type u_3
α : Type u_4
β : Type u_5
inst✝⁶ : MeasurableSpace X
inst✝⁵ : SMul M X
m : MeasurableSpace α
mβ : MeasurableSpace β
μ : Measure α
f : α → M
g : α → X
inst✝⁴ : MeasurableConstSMul M X
inst✝³ : SMul M α
inst✝² : SMul Mᵐᵒᵖ α
inst✝¹ : IsCentralScalar M α
inst✝ : MeasurableConstSMul M α
⊢ ∀ (a : M), Measurable fun x ↦ a • x
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: β : Type u_5
α : Type u_6
inst✝⁴ : MeasurableSpace β
inst✝³ : MeasurableSpace α
f : α → β
G : Type u_7
inst✝² : Group G
inst✝¹ : MulAction G β
inst✝ : MeasurableConstSMul G β
c : G
h : Measurable fun x ↦ c • f x
⊢ Measurable f

Tactic:
simpa using

Goal state after:
β : Type u_5
α : Type u_6
inst✝⁴ : MeasurableSpace β
inst✝³ : MeasurableSpace α
f : α → β
G : Type u_7
inst✝² : Group G
inst✝¹ : MulAction G β
inst✝ : MeasurableConstSMul G β
c : G
h : Measurable fun x ↦ c • f x
⊢ Measurable f
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Basic

Goal state before:
pp: α✝ : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s t u : Set α✝
α : Type u_6
inst✝¹ : TopologicalSpace α
inst✝ : MeasurableSpace α
hα : BorelSpace α
p : α → Prop
⊢ instMeasurableSpace = borel (Subtype p)

Tactic:
by borelize α; symm; apply borel_comap

Goal state after:
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: β : Type u_5
α : Type u_6
inst✝⁴ : MeasurableSpace β
inst✝³ : MeasurableSpace α
f : α → β
μ : Measure α
G : Type u_7
inst✝² : Group G
inst✝¹ : MulAction G β
inst✝ : MeasurableConstSMul G β
c : G
h : AEMeasurable (fun x ↦ c • f x) μ
⊢ AEMeasurable f μ

Tactic:
simpa using

Goal state after:
β : Type u_5
α : Type u_6
inst✝⁴ : MeasurableSpace β
inst✝³ : MeasurableSpace α
f : α → β
μ : Measure α
G : Type u_7
inst✝² : Group G
inst✝¹ : MulAction G β
inst✝ : MeasurableConstSMul G β
c : G
h : AEMeasurable (fun x ↦ c • f x) μ
⊢ AEMeasurable f μ
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
α : Type u_3
inst✝² : Monoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
l : List (α → M)
hl : ∀ f ∈ l, Measurable f
⊢ Measurable fun x ↦ (map (fun f ↦ f x) l).prod

Tactic:
simpa using

Goal state after:
M : Type u_2
α : Type u_3
inst✝² : Monoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
l : List (α → M)
hl : ∀ f ∈ l, Measurable f
⊢ Measurable fun x ↦ l.prod x
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
α : Type u_3
inst✝² : Monoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
l : List (α → M)
hl : ∀ f ∈ l, AEMeasurable f μ
⊢ AEMeasurable (fun x ↦ (map (fun f ↦ f x) l).prod) μ

Tactic:
simpa using

Goal state after:
M : Type u_2
α : Type u_3
inst✝² : Monoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
l : List (α → M)
hl : ∀ f ∈ l, AEMeasurable f μ
⊢ AEMeasurable (fun x ↦ l.prod x) μ
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: case mk
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, Measurable f
⊢ Measurable (prod (Quot.mk (⇑(List.isSetoid (α → M))) l))

Tactic:
simpa using

Goal state after:
case mk
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, Measurable f
⊢ Measurable l.prod
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, Measurable f
⊢ ∀ f ∈ l, Measurable f

Tactic:
simpa using

Goal state after:
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, Measurable f
⊢ ∀ f ∈ l, Measurable f
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: case mk
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, AEMeasurable f μ
⊢ AEMeasurable (prod (Quot.mk (⇑(List.isSetoid (α → M))) l)) μ

Tactic:
simpa using

Goal state after:
case mk
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, AEMeasurable f μ
⊢ AEMeasurable l.prod μ
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, AEMeasurable f μ
⊢ ∀ f ∈ l, AEMeasurable f μ

Tactic:
simpa using

Goal state after:
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
l✝ : Multiset (α → M)
l : List (α → M)
hl : ∀ f ∈ Quot.mk (⇑(List.isSetoid (α → M))) l, AEMeasurable f μ
⊢ ∀ f ∈ l, AEMeasurable f μ
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
s : Multiset (α → M)
hs : ∀ f ∈ s, Measurable f
⊢ Measurable fun x ↦ (map (fun f ↦ f x) s).prod

Tactic:
simpa using

Goal state after:
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
s : Multiset (α → M)
hs : ∀ f ∈ s, Measurable f
⊢ Measurable fun x ↦ s.prod x
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
s : Multiset (α → M)
hs : ∀ f ∈ s, AEMeasurable f μ
⊢ AEMeasurable (fun x ↦ (map (fun f ↦ f x) s).prod) μ

Tactic:
simpa using

Goal state after:
M : Type u_2
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
s : Multiset (α → M)
hs : ∀ f ∈ s, AEMeasurable f μ
⊢ AEMeasurable (fun x ↦ s.prod x) μ
Module: Mathlib.MeasureTheory.Group.Arithmetic

Goal state before:
pp: M : Type u_2
ι : Type u_3
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
f : ι → α → M
s : Finset ι
hf : ∀ i ∈ s, AEMeasurable (f i) μ
⊢ AEMeasurable (fun a ↦ ∏ i ∈ s, f i a) μ

Tactic:
simpa using

Goal state after:
M : Type u_2
ι : Type u_3
α : Type u_4
inst✝² : CommMonoid M
inst✝¹ : MeasurableSpace M
inst✝ : MeasurableMul₂ M
m : MeasurableSpace α
μ : Measure α
f : ι → α → M
s : Finset ι
hf : ∀ i ∈ s, AEMeasurable (f i) μ
⊢ AEMeasurable (fun a ↦ (∏ c ∈ s, f c) a) μ
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Basic

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s t u : Set α
inst✝¹³ : TopologicalSpace α
inst✝¹² : MeasurableSpace α
inst✝¹¹ : OpensMeasurableSpace α
inst✝¹⁰ : TopologicalSpace β
inst✝⁹ : MeasurableSpace β
inst✝⁸ : OpensMeasurableSpace β
inst✝⁷ : TopologicalSpace γ
inst✝⁶ : MeasurableSpace γ
inst✝⁵ : BorelSpace γ
inst✝⁴ : TopologicalSpace γ₂
inst✝³ : MeasurableSpace γ₂
inst✝² : BorelSpace γ₂
inst✝¹ : MeasurableSpace δ
inst✝ : T0Space α
x y : α
hxy : ∀ (s : Set α), MeasurableSet s → (x ∈ s ↔ y ∈ s)
⊢ Inseparable x y

Tactic:
inseparable_iff_forall_isOpen

Goal state after:
α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s t u : Set α
inst✝¹³ : TopologicalSpace α
inst✝¹² : MeasurableSpace α
inst✝¹¹ : OpensMeasurableSpace α
inst✝¹⁰ : TopologicalSpace β
inst✝⁹ : MeasurableSpace β
inst✝⁸ : OpensMeasurableSpace β
inst✝⁷ : TopologicalSpace γ
inst✝⁶ : MeasurableSpace γ
inst✝⁵ : BorelSpace γ
inst✝⁴ : TopologicalSpace γ₂
inst✝³ : MeasurableSpace γ₂
inst✝² : BorelSpace γ₂
inst✝¹ : MeasurableSpace δ
inst✝ : T0Space α
x y : α
hxy : ∀ (s : Set α), MeasurableSet s → (x ∈ s ↔ y ∈ s)
⊢ ∀ (s : Set α), IsOpen[inst✝¹³] s → (x ∈ s ↔ y ∈ s)
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Order

Goal state before:
pp: α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : SecondCountableTopology α
inst✝¹ : LinearOrder α
inst✝ : OrderTopology α
this : MeasurableSpace α := MeasurableSpace.generateFrom (range Iio)
H : ∀ (a : α), MeasurableSet (Iio a)
a : α
hcovBy : ¬∃ b, a ⋖ b
t : Set α
hat : t ⊆ Ioi a
htc : t.Countable
htU : ⋃ i ∈ t, Ioi i = ⋃ i ∈ Ioi a, Ioi i
⊢ Ioi a ⊆ ⋃ i ∈ t, Ioi i

Tactic:
simpa using

Goal state after:
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : SecondCountableTopology α
inst✝¹ : LinearOrder α
inst✝ : OrderTopology α
this : MeasurableSpace α := MeasurableSpace.generateFrom (range Iio)
H : ∀ (a : α), MeasurableSet (Iio a)
a : α
hcovBy : ¬∃ b, a ⋖ b
t : Set α
hat : t ⊆ Ioi a
htc : t.Countable
htU : ⋃ i ∈ t, Ioi i = ⋃ i ∈ Ioi a, Ioi i
⊢ ∀ (x : α), a < x → ∃ i, a < i ∧ i < x
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Basic

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s✝ t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
s : Set (α × β)
hs : IsOpen[instTopologicalSpaceProd] s
hα : SecondCountableTopology α
F : Set α → Set β := fun a ↦ {y | ∃ b, IsOpen[inst✝⁹] b ∧ y ∈ b ∧ a ×ˢ b ⊆ s}
A : ∀ (a : Set α), IsOpen[inst✝⁹] (F a)
⊢ s = ⋃ a ∈ countableBasis α, a ×ˢ F a

Tactic:
apply Subset.antisymm

Goal state after:
case h₁
α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s✝ t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
s : Set (α × β)
hs : IsOpen[instTopologicalSpaceProd] s
hα : SecondCountableTopology α
F : Set α → Set β := ⋯
A : ∀ (a : Set α), IsOpen[inst✝⁹] (F a)
⊢ s ⊆ ⋃ a ∈ countableBasis α, a ×ˢ F a

case h₂
α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s✝ t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
s : Set (α × β)
hs : IsOpen[instTopologicalSpaceProd] s
hα : SecondCountableTopology α
F : Set α → Set β := ⋯
A : ∀ (a : Set α), IsOpen[inst✝⁹] (F a)
⊢ ⋃ a ∈ countableBasis α, a ×ˢ F a ⊆ s
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) < ∞
⊢ 0 < ↑ε / 2

Tactic:
simpa using

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) < ∞
⊢ ¬ε = 0
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) < ∞
ε0 : 0 < ↑ε / 2
this :
  infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) <
    infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε / 2
y : α
ycs : y ∈ closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s
hy : edist x y < infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε / 2
z : α
zs : z ∈ s
dyz : edist y z < ↑ε / 2
⊢ infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + (↑ε / 2 + ↑ε / 2) =
    infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε

Tactic:
ENNReal.add_halves

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) < ∞
ε0 : 0 < ↑ε / 2
this :
  infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) <
    infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε / 2
y : α
ycs : y ∈ closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s
hy : edist x y < infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε / 2
z : α
zs : z ∈ s
dyz : edist y z < ↑ε / 2
⊢ infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε =
    infEDist x (closure[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] s) + ↑ε
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
U : Set α
hU : IsOpen[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] U
a : ℝ≥0∞
a_pos : 0 < a
a_lt_one : a < 1
F : ℕ → Set α := fun n ↦ (fun x ↦ infEDist x Uᶜ) ⁻¹' Ici (a ^ n)
F_subset : ∀ (n : ℕ), F n ⊆ U
x : α
hx : x ∈ U
⊢ x ∉ Uᶜ

Tactic:
simpa using

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
U : Set α
hU : IsOpen[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] U
a : ℝ≥0∞
a_pos : 0 < a
a_lt_one : a < 1
F : ℕ → Set α := fun n ↦ (fun x ↦ infEDist x Uᶜ) ⁻¹' Ici (a ^ n)
F_subset : ∀ (n : ℕ), F n ⊆ U
x : α
hx : x ∈ U
⊢ x ∈ U
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Basic

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s✝ t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
s : Set (α × β)
hs : IsOpen[instTopologicalSpaceProd] s
hβ : SecondCountableTopology β
F : Set β → Set α := fun a ↦ {y | ∃ b, IsOpen[inst✝¹²] b ∧ y ∈ b ∧ b ×ˢ a ⊆ s}
A : ∀ (a : Set β), IsOpen[inst✝¹²] (F a)
⊢ s = ⋃ a ∈ countableBasis β, F a ×ˢ a

Tactic:
apply Subset.antisymm

Goal state after:
case h₁
α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s✝ t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
s : Set (α × β)
hs : IsOpen[instTopologicalSpaceProd] s
hβ : SecondCountableTopology β
F : Set β → Set α := ⋯
A : ∀ (a : Set β), IsOpen[inst✝¹²] (F a)
⊢ s ⊆ ⋃ a ∈ countableBasis β, F a ×ˢ a

case h₂
α : Type u_1
β : Type u_2
γ : Type u_3
γ₂ : Type u_4
δ : Type u_5
ι : Sort y
s✝ t u : Set α
inst✝¹² : TopologicalSpace α
inst✝¹¹ : MeasurableSpace α
inst✝¹⁰ : OpensMeasurableSpace α
inst✝⁹ : TopologicalSpace β
inst✝⁸ : MeasurableSpace β
inst✝⁷ : OpensMeasurableSpace β
inst✝⁶ : TopologicalSpace γ
inst✝⁵ : MeasurableSpace γ
inst✝⁴ : BorelSpace γ
inst✝³ : TopologicalSpace γ₂
inst✝² : MeasurableSpace γ₂
inst✝¹ : BorelSpace γ₂
inst✝ : MeasurableSpace δ
h : SecondCountableTopologyEither α β
s : Set (α × β)
hs : IsOpen[instTopologicalSpaceProd] s
hβ : SecondCountableTopology β
F : Set β → Set α := ⋯
A : ∀ (a : Set β), IsOpen[inst✝¹²] (F a)
⊢ ⋃ a ∈ countableBasis β, F a ×ˢ a ⊆ s
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
U : Set α
hU : IsOpen[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] U
a : ℝ≥0∞
a_pos : 0 < a
a_lt_one : a < 1
F : ℕ → Set α := fun n ↦ (fun x ↦ infEDist x Uᶜ) ⁻¹' Ici (a ^ n)
F_subset : ∀ (n : ℕ), F n ⊆ U
x : α
hx : x ∈ U
this : ¬infEDist x Uᶜ = 0
⊢ 0 < infEDist x Uᶜ

Tactic:
simpa using

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
U : Set α
hU : IsOpen[PseudoEMetricSpace.toUniformSpace.toTopologicalSpace] U
a : ℝ≥0∞
a_pos : 0 < a
a_lt_one : a < 1
F : ℕ → Set α := fun n ↦ (fun x ↦ infEDist x Uᶜ) ⁻¹' Ici (a ^ n)
F_subset : ∀ (n : ℕ), F n ⊆ U
x : α
hx : x ∈ U
this : ¬infEDist x Uᶜ = 0
⊢ ¬infEDist x Uᶜ = 0
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Order

Goal state before:
pp: α : Type u_5
inst✝³ : TopologicalSpace α
inst✝² : SecondCountableTopology α
inst✝¹ : LinearOrder α
inst✝ : OrderTopology α
⊢ borel α = MeasurableSpace.generateFrom {S | ∃ l u, l ≤ u ∧ Icc l u = S}

Tactic:
simpa using

Goal state after:
α : Type u_5
inst✝³ : TopologicalSpace α
inst✝² : SecondCountableTopology α
inst✝¹ : LinearOrder α
inst✝ : OrderTopology α
⊢ borel α = MeasurableSpace.generateFrom {S | ∃ l u, l ≤ u ∧ Icc l u = S}
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s t : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x s + hausdorffEDist s t < ∞
⊢ ↑ε / 2 ≠ 0

Tactic:
simpa using

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s t : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x s + hausdorffEDist s t < ∞
⊢ ¬ε = 0
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s t : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x s + hausdorffEDist s t < ∞
ε0 : ↑ε / 2 ≠ 0
this✝ : infEDist x s < infEDist x s + ↑ε / 2
y : α
ys : y ∈ s
dxy : edist x y < infEDist x s + ↑ε / 2
this : hausdorffEDist s t < hausdorffEDist s t + ↑ε / 2
z : α
zt : z ∈ t
dyz : edist y z < hausdorffEDist s t + ↑ε / 2
⊢ infEDist x s + hausdorffEDist s t + (↑ε / 2 + ↑ε / 2) = infEDist x s + hausdorffEDist s t + ↑ε

Tactic:
ENNReal.add_halves

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
x : α
s t : Set α
ε : ℝ≥0
εpos : 0 < ε
h : infEDist x s + hausdorffEDist s t < ∞
ε0 : ↑ε / 2 ≠ 0
this✝ : infEDist x s < infEDist x s + ↑ε / 2
y : α
ys : y ∈ s
dxy : edist x y < infEDist x s + ↑ε / 2
this : hausdorffEDist s t < hausdorffEDist s t + ↑ε / 2
z : α
zt : z ∈ t
dyz : edist y z < hausdorffEDist s t + ↑ε / 2
⊢ infEDist x s + hausdorffEDist s t + ↑ε = infEDist x s + hausdorffEDist s t + ↑ε
Module: Mathlib.MeasureTheory.Constructions.BorelSpace.Basic

Goal state before:
pp: α : Type u_6
β : Type u_7
inst✝³ : MeasurableSpace α
inst✝² : TopologicalSpace α
inst✝¹ : MeasurableSpace β
inst✝ : TopologicalSpace β
hβ : BorelSpace β
e : α → β
h'e : MeasurableEmbedding e
h''e : IsInducing e
⊢ MeasurableSpace.comap e (borel β) = inst✝³

Tactic:
simpa using

Goal state after:
α : Type u_6
β : Type u_7
inst✝³ : MeasurableSpace α
inst✝² : TopologicalSpace α
inst✝¹ : MeasurableSpace β
inst✝ : TopologicalSpace β
hβ : BorelSpace β
e : α → β
h'e : MeasurableEmbedding e
h''e : IsInducing e
⊢ MeasurableSpace.comap e (borel β) = inst✝³
Module: Mathlib.Topology.MetricSpace.HausdorffDistance

Goal state before:
pp: case left
α : Type u
inst✝ : PseudoEMetricSpace α
s t u : Set α
⊢ ∀ x ∈ s, infEDist x u ≤ hausdorffEDist s t + hausdorffEDist t u

Tactic:
exact fun x xs =>
      calc
        infEDist x u ≤ infEDist x t + hausdorffEDist t u :=
          infEDist_le_infEDist_add_hausdorffEDist
        _ ≤ hausdorffEDist s t + hausdorffEDist t u := by grw [infEDist_le_hausdorffEDist_of_mem xs]

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

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
E : Set α
x : α
x_in_E : x ∈ E
y : α
hy : ENNReal.ofReal δ ≤ infEDist y E
⊢ ENNReal.ofReal δ ≤ edist x y

Tactic:
simpa using

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
E : Set α
x : α
x_in_E : x ∈ E
y : α
hy : ENNReal.ofReal δ ≤ infEDist y E
⊢ ENNReal.ofReal δ ≤ edist x y
Module: Mathlib.Topology.MetricSpace.Thickening

Goal state before:
pp: α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
E : Set α
⊢ Eᶜᶜ ⊆ (thickening δ (thickening δ E)ᶜ)ᶜ

Tactic:
simpa using

Goal state after:
α : Type u
inst✝ : PseudoEMetricSpace α
δ : ℝ
E : Set α
⊢ E ⊆ (thickening δ (thickening δ E)ᶜ)ᶜ