Theorem: MeasureTheory.Measure.ext_of_generateFrom_of_iUnion
File: Mathlib/MeasureTheory/Measure/Restrict.lean

tactic: refine ext_of_generateFrom_of_cover_subset hA hC ?_ (countable_range B) h1B ?_ h_eq
state_before: R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
⊢ μ = ν
state_after: case refine_1
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
⊢ range B ⊆ C

case refine_2
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
⊢ ∀ s ∈ range B, μ s ≠ ⊤

tactic: rintro _ ⟨i, rfl⟩
state_before: case refine_1
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
⊢ range B ⊆ C
state_after: case refine_1.intro
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
i : ℕ
⊢ B i ∈ C

tactic: apply h2B
state_before: case refine_1.intro
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
i : ℕ
⊢ B i ∈ C
state_after: no goals

tactic: rintro _ ⟨i, rfl⟩
state_before: case refine_2
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
⊢ ∀ s ∈ range B, μ s ≠ ⊤
state_after: case refine_2.intro
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
i : ℕ
⊢ μ (B i) ≠ ⊤

tactic: apply hμB
state_before: case refine_2.intro
R : Type u_1
α : Type u_2
β : Type u_3
δ : Type u_4
γ : Type u_5
ι : Type u_6
m0 : MeasurableSpace α
inst✝¹ : MeasurableSpace β
inst✝ : MeasurableSpace γ
μ μ₁ μ₂ μ₃ ν ν' ν₁ ν₂ : Measure α
s s' t : Set α
C : Set (Set α)
B : ℕ → Set α
hA : m0 = generateFrom C
hC : IsPiSystem C
h1B : ⋃ i, B i = univ
h2B : ∀ (i : ℕ), B i ∈ C
hμB : ∀ (i : ℕ), μ (B i) ≠ ⊤
h_eq : ∀ s ∈ C, μ s = ν s
i : ℕ
⊢ μ (B i) ≠ ⊤
state_after: no goals