mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Lemmas

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹⁰ : CommRing R
inst✝⁹ : CharZero R
inst✝⁸ : IsDomain R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : Finite ι
inst✝² : P.IsCrystallographic
b : P.Base
i j k l m : ι
inst✝¹ : P.IsReduced
inst✝ : P.IsIrreducible
hi : i ∈ b.support
hj : j ∈ b.support
hij : i ≠ j
h₁ : P.root k + P.root i = P.root l
h₂ : P.root k - P.root j = P.root m
hki : P.pairingIn ℤ k i = 0
this✝² : Module.IsReflexive R M := Module.IsReflexive.of_isPerfPair P.toLinearMap
him_mem : P.root i + P.root m ∈ range ⇑P.root
hjl_mem : P.root j + P.root (-l) ∈ range ⇑P.root
hjk_mem : P.root j + P.root (-k) ∈ range ⇑P.root
this✝¹ : P.IsNotG2
this✝ : InvolutiveNeg ι := P.indexNeg
this : IsAddTorsionFree M
n : ι
hn : P.root n = P.root k + P.root i - P.root j
hnk_ne : n ≠ k
hkj_ne : k ≠ j ∧ P.root k ≠ -P.root j
hnk_notMem : P.root n - P.root k ∉ range ⇑P.root
aux₀ : P.pairingIn ℤ j i = -P.pairingIn ℤ m i
aux₁ : P.pairingIn ℤ j i = 0
key₁ : P.pairingIn ℤ i k = 0
key₂ : P.pairingIn ℤ i m = 0
key₃ : P.pairingIn ℤ j k = 2
key₄ : P.pairingIn ℤ j l ≠ 0
hik_mem : P.root i + P.root k ∈ range ⇑P.root
⊢ ((if P.pairingIn ℤ i m = 0 then 1 else 0) + 1) * ((if P.pairingIn ℤ j (-k) = 0 then 1 else 0) + 1) =
    ((if P.pairingIn ℤ j (-l) = 0 then 1 else 0) + 1) * ((if P.pairingIn ℤ i k = 0 then 1 else 0) + 1)

Tactic:
simp [key₁, key₂, key₃, key₄]

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Relations

Goal state before:
pp: case inr
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁹ : Finite ι
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
inst✝⁶ : CharZero R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : P.IsCrystallographic
b : P.Base
inst✝ : Fintype ι
i j : ↥b.support
hij : i ≠ j
this : InvolutiveNeg ι := P.indexNeg
k : ι
aux : ⁅e i, f j⁆ (Sum.inr k) (Sum.inr (-↑i)) = (⁅e i, f j⁆ * ω b) (Sum.inr k) (Sum.inr ↑i)
⊢ (⁅e i, f j⁆ * ω b) (Sum.inr k) (Sum.inr ↑i) = 0 (Sum.inr k)

Tactic:
lie_e_f_mul_ω,

Goal state after:
case inr
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁹ : Finite ι
inst✝⁸ : CommRing R
inst✝⁷ : IsDomain R
inst✝⁶ : CharZero R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : AddCommGroup N
inst✝² : Module R N
P : RootPairing ι R M N
inst✝¹ : P.IsCrystallographic
b : P.Base
inst✝ : Fintype ι
i j : ↥b.support
hij : i ≠ j
this : InvolutiveNeg ι := P.indexNeg
k : ι
aux : ⁅e i, f j⁆ (Sum.inr k) (Sum.inr (-↑i)) = (⁅e i, f j⁆ * ω b) (Sum.inr k) (Sum.inr ↑i)
⊢ (-ω b * ⁅e j, f i⁆) (Sum.inr k) (Sum.inr ↑i) = 0 (Sum.inr k)
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Relations

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹¹ : Finite ι
inst✝¹⁰ : CommRing R
inst✝⁹ : IsDomain R
inst✝⁸ : CharZero R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.IsCrystallographic
b : P.Base
inst✝² : Fintype ι
i j : ↥b.support
hij : i ≠ j
inst✝¹ : P.IsReduced
inst✝ : P.IsIrreducible
hij' : ↑i ≠ ↑j
this✝ : InvolutiveNeg ι := P.indexNeg
k l : ι
h₃ : l ≠ ↑j
h₄ : l ≠ -↑i
this :
  (∑ x,
      if P.root x = P.root l - P.root ↑j ∧ P.root k = P.root ↑i + P.root x then
        (↑(chainBotCoeff (↑i) x) + 1) * (↑(chainTopCoeff (↑j) l) + 1)
      else 0) =
    ∑ x,
      if P.root x = P.root ↑i + P.root l ∧ P.root k = P.root x - P.root ↑j then
        (↑(chainTopCoeff (↑j) x) + 1) * (↑(chainBotCoeff (↑i) l) + 1)
      else 0
contra : l = -↑i
⊢ False

Tactic:
contradiction

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Relations

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝¹¹ : Finite ι
inst✝¹⁰ : CommRing R
inst✝⁹ : IsDomain R
inst✝⁸ : CharZero R
inst✝⁷ : AddCommGroup M
inst✝⁶ : Module R M
inst✝⁵ : AddCommGroup N
inst✝⁴ : Module R N
P : RootPairing ι R M N
inst✝³ : P.IsCrystallographic
b : P.Base
inst✝² : Fintype ι
i j : ↥b.support
hij : i ≠ j
inst✝¹ : P.IsReduced
inst✝ : P.IsIrreducible
hij' : ↑i ≠ ↑j
this✝ : InvolutiveNeg ι := P.indexNeg
k l : ι
h₃ : l ≠ ↑j
h₄ : l ≠ -↑i
this :
  (∑ x,
      if P.root x = P.root l - P.root ↑j ∧ P.root k = P.root ↑i + P.root x then
        (↑(chainBotCoeff (↑i) x) + 1) * (↑(chainTopCoeff (↑j) l) + 1)
      else 0) =
    ∑ x,
      if P.root x = P.root ↑i + P.root l ∧ P.root k = P.root x - P.root ↑j then
        (↑(chainTopCoeff (↑j) x) + 1) * (↑(chainBotCoeff (↑i) l) + 1)
      else 0
h₁ : ∀ x ∈ Finset.univ, ¬((x = i ∧ l = -↑i) ∧ k = -↑j)
contra : l = ↑j
⊢ False

Tactic:
contradiction

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.GeckConstruction.Semisimple

Goal state before:
pp: ι : Type u_1
K : Type u_2
M : Type u_3
N : Type u_4
inst✝¹² : Field K
inst✝¹¹ : CharZero K
inst✝¹⁰ : DecidableEq ι
inst✝⁹ : Fintype ι
inst✝⁸ : AddCommGroup M
inst✝⁷ : Module K M
inst✝⁶ : AddCommGroup N
inst✝⁵ : Module K N
P : RootPairing ι K M N
inst✝⁴ : P.IsRootSystem
inst✝³ : P.IsCrystallographic
b : P.Base
inst✝² : P.IsReduced
inst✝¹ : P.IsIrreducible
inst✝ : Nonempty ι
U : LieSubmodule K (↥(lieAlgebra b)) (↥b.support ⊕ ι → K)
U' : LieSubmodule K (↥H) (↥b.support ⊕ ι → K) := { toSubmodule := ↑U, lie_mem := ⋯ }
hU : ↑U ≤ span K (range u)
x : ↥b.support ⊕ ι → K
hx : x ∈ U
c : ↥b.support → K
hc : ∑ i, c i • u i = x
hCM : c ≠ 0
j : ↥b.support
contra : ¬∑ k, c k * ↑|b.cartanMatrix j k| = 0
key : v b ↑j ∈ U
this : v b ↑j ∉ U
⊢ False

Tactic:
contradiction

Goal state after:
Module: Mathlib.LinearAlgebra.TensorAlgebra.Grading

Goal state before:
pp: case add
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
i✝ : ℕ
x✝ x y : TensorAlgebra R M
i : ℕ
hx : x ∈ (ι R).range ^ i
hy : y ∈ (ι R).range ^ i
ihx : ((lift R) (GradedAlgebra.ι R M)) x = (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨x, hx⟩
ihy : ((lift R) (GradedAlgebra.ι R M)) y = (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨y, hy⟩
⊢ ((lift R) (GradedAlgebra.ι R M)) x + ((lift R) (GradedAlgebra.ι R M)) y =
    (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨x + y, ⋯⟩

Tactic:
ihx,

Goal state after:
case add
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
i✝ : ℕ
x✝ x y : TensorAlgebra R M
i : ℕ
hx : x ∈ (ι R).range ^ i
hy : y ∈ (ι R).range ^ i
ihx : ((lift R) (GradedAlgebra.ι R M)) x = (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨x, hx⟩
ihy : ((lift R) (GradedAlgebra.ι R M)) y = (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨y, hy⟩
⊢ (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨x, hx⟩ + ((lift R) (GradedAlgebra.ι R M)) y =
    (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨x + y, ⋯⟩
Module: Mathlib.LinearAlgebra.TensorAlgebra.Grading

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
i : ℕ
x : TensorAlgebra R M
hx : x ∈ (ι R).range ^ i
⊢ ((lift R) (GradedAlgebra.ι R M)) x = (DirectSum.of (fun i ↦ ↥((ι R).range ^ i)) i) ⟨x, hx⟩

Tactic:
induction hx using Submodule.pow_induction_on_left' with

Goal state after:
Module: Mathlib.LinearAlgebra.TensorProduct.Matrix

Goal state before:
pp: R : Type u_1
M : Type u_2
N : Type u_3
M' : Type u_5
N' : Type u_6
ι : Type u_7
κ : Type u_8
ι' : Type u_10
κ' : Type u_11
inst✝¹⁴ : DecidableEq ι
inst✝¹³ : DecidableEq κ
inst✝¹² : Fintype ι
inst✝¹¹ : Fintype κ
inst✝¹⁰ : Finite ι'
inst✝⁹ : Finite κ'
inst✝⁸ : CommRing R
inst✝⁷ : AddCommGroup M
inst✝⁶ : AddCommGroup N
inst✝⁵ : AddCommGroup M'
inst✝⁴ : AddCommGroup N'
inst✝³ : Module R M
inst✝² : Module R N
inst✝¹ : Module R M'
inst✝ : Module R N'
bM : Basis ι R M
bN : Basis κ R N
bM' : Basis ι' R M'
bN' : Basis κ' R N'
f : M →ₗ[R] M'
g : N →ₗ[R] N'
i : ι'
j : κ'
i' : ι
j' : κ
⊢ ((bM'.tensorProduct bN').repr (f (bM i') ⊗ₜ[R] g (bN j'))) (i, j) =
    (bM'.repr (f (bM i'))) i * (bN'.repr (g (bN j'))) j

Tactic:
Basis.tensorProduct_repr_tmul_apply

Goal state after:
R : Type u_1
M : Type u_2
N : Type u_3
M' : Type u_5
N' : Type u_6
ι : Type u_7
κ : Type u_8
ι' : Type u_10
κ' : Type u_11
inst✝¹⁴ : DecidableEq ι
inst✝¹³ : DecidableEq κ
inst✝¹² : Fintype ι
inst✝¹¹ : Fintype κ
inst✝¹⁰ : Finite ι'
inst✝⁹ : Finite κ'
inst✝⁸ : CommRing R
inst✝⁷ : AddCommGroup M
inst✝⁶ : AddCommGroup N
inst✝⁵ : AddCommGroup M'
inst✝⁴ : AddCommGroup N'
inst✝³ : Module R M
inst✝² : Module R N
inst✝¹ : Module R M'
inst✝ : Module R N'
bM : Basis ι R M
bN : Basis κ R N
bM' : Basis ι' R M'
bN' : Basis κ' R N'
f : M →ₗ[R] M'
g : N →ₗ[R] N'
i : ι'
j : κ'
i' : ι
j' : κ
⊢ (bN'.repr (g (bN j'))) j • (bM'.repr (f (bM i'))) i = (bM'.repr (f (bM i'))) i * (bN'.repr (g (bN j'))) j
Module: Mathlib.Logic.Hydra

Goal state before:
pp: case refine_2
α : Type u_1
r : α → α → Prop
inst✝¹ : DecidableEq α
inst✝ : Std.Irrefl r
s' s t : Multiset α
a : α
⊢ (∀ a' ∈ t, r a' a) ∧ a ∈ s ∧ s' = s.erase a + t → (∀ a' ∈ t, r a' a) ∧ a ∈ s + t ∧ s' = (s + t).erase a

Tactic:
rintro ⟨ht, h, rfl⟩

Goal state after:
case refine_2
α : Type u_1
r : α → α → Prop
inst✝¹ : DecidableEq α
inst✝ : Std.Irrefl r
s t : Multiset α
a : α
ht : ∀ a' ∈ t, r a' a
h : a ∈ s
⊢ (∀ a' ∈ t, r a' a) ∧ a ∈ s + t ∧ s.erase a + t = (s + t).erase a
Module: Mathlib.MeasureTheory.Constructions.Projective

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
h : IsEmpty ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
I : Finset ι
i : ι
hi : IsEmpty (α i)
this : IsEmpty ((j : ↥(insert i I)) → α ↑j)
⊢ Measure.map (Finset.restrict₂ ⋯) (P (insert i I)) = 0

Tactic:
rw [(P (insert i I)).eq_zero_of_isEmpty]

Goal state after:
ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
h : IsEmpty ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
I : Finset ι
i : ι
hi : IsEmpty (α i)
this : IsEmpty ((j : ↥(insert i I)) → α ↑j)
⊢ Measure.map (Finset.restrict₂ ⋯) 0 = 0
Module: Mathlib.MeasureTheory.Constructions.Projective

Goal state before:
pp: case inr
ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
hJI : J ⊆ I
h : Nonempty ((i : ι) → α i)
this : S = Finset.restrict₂ hJI ⁻¹' T
⊢ (P I) S = (Measure.map (Finset.restrict₂ hJI) (P I)) T

Tactic:
Measure.map_apply _ hT,

Goal state after:
case inr
ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
hJI : J ⊆ I
h : Nonempty ((i : ι) → α i)
this : S = Finset.restrict₂ hJI ⁻¹' T
⊢ (P I) S = (P I) (Finset.restrict₂ hJI ⁻¹' T)

ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
hJI : J ⊆ I
h : Nonempty ((i : ι) → α i)
this : S = Finset.restrict₂ hJI ⁻¹' T
⊢ Measurable (Finset.restrict₂ hJI)
Module: Mathlib.MeasureTheory.Constructions.Projective

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hS : MeasurableSet S
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
U : Set ((i : ↥(I ∪ J)) → α ↑i) := Finset.restrict₂ ⋯ ⁻¹' S ∩ Finset.restrict₂ ⋯ ⁻¹' T
⊢ cylinder I S = cylinder (I ∪ J) U

Tactic:
← inter_cylinder,

Goal state after:
ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hS : MeasurableSet S
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
U : Set ((i : ↥(I ∪ J)) → α ↑i) := Finset.restrict₂ ⋯ ⁻¹' S ∩ Finset.restrict₂ ⋯ ⁻¹' T
⊢ cylinder I S = cylinder I S ∩ cylinder J T
Module: Mathlib.MeasureTheory.Constructions.Projective

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hS : MeasurableSet S
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
U : Set ((i : ↥(I ∪ J)) → α ↑i) := Finset.restrict₂ ⋯ ⁻¹' S ∩ Finset.restrict₂ ⋯ ⁻¹' T
⊢ cylinder J T = cylinder (I ∪ J) U

Tactic:
← inter_cylinder,

Goal state after:
ι : Type u_1
α : ι → Type u_2
inst✝ : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
I J : Finset ι
hP : IsProjectiveMeasureFamily P
S : Set ((i : ↥I) → α ↑i)
T : Set ((i : ↥J) → α ↑i)
hS : MeasurableSet S
hT : MeasurableSet T
h_eq : cylinder I S = cylinder J T
U : Set ((i : ↥(I ∪ J)) → α ↑i) := Finset.restrict₂ ⋯ ⁻¹' S ∩ Finset.restrict₂ ⋯ ⁻¹' T
⊢ cylinder J T = cylinder I S ∩ cylinder J T
Module: Mathlib.MeasureTheory.SetSemiring

Goal state before:
pp: case insert
α : Type u_1
C : Set (Set α)
ι : Type u_2
hC : IsSetRing C
s : ι → Set α
i : ι
S : Finset ι
a✝ : i ∉ S
h : (∀ n ∈ S, s n ∈ C) → ⋃ i ∈ S, s i ∈ C
hs : ∀ n ∈ insert i S, s n ∈ C
⊢ ⋃ i_1 ∈ ↑(insert i S), s i_1 ∈ C

Tactic:
Finset.coe_insert,

Goal state after:
case insert
α : Type u_1
C : Set (Set α)
ι : Type u_2
hC : IsSetRing C
s : ι → Set α
i : ι
S : Finset ι
a✝ : i ∉ S
h : (∀ n ∈ S, s n ∈ C) → ⋃ i ∈ S, s i ∈ C
hs : ∀ n ∈ insert i S, s n ∈ C
⊢ ⋃ i_1 ∈ insert i ↑S, s i_1 ∈ C
Module: Mathlib.MeasureTheory.SetSemiring

Goal state before:
pp: α : Type u_1
C : Set (Set α)
s : Set α
I : Finset (Set α)
hC : IsSetSemiring C
hs : s ∈ C
hI : ↑I ⊆ C
hC' : IsSetRing (supClosure C)
⊢ s \ I.sup id ∈ supClosure C

Tactic:
exact hC'.sdiff_mem (subset_supClosure hs) <| hC'.finsetSup_mem <| hI.trans subset_supClosure

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

Goal state before:
pp: case a.inl.coe.top.inl.refine_2
ι : Type u_1
inst✝¹ : Preorder ι
ts : TopologicalSpace ι
ht : OrderTopology ι
inst✝ : SecondCountableTopology ι
x₀ : ι
c : Set ι
c_count : c.Countable
hc : ts = generateFrom {s | ∃ a ∈ c, s = Ioi a ∨ s = Iio a}
c' : Set ι
c'_count : c'.Countable
hc' : Dense c'
x₁ : ι := if h : ∃ x, Ioi x = ∅ then h.choose else x₀
d : Set (WithTop ι) := WithTop.some '' c ∪ WithTop.some '' c' ∪ {⊤} ∪ {↑x₁}
basis : Set (Set ι) := {s | ∃ f g, f ⊆ c ∧ g ⊆ c ∧ f.Finite ∧ g.Finite ∧ s = (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a}
h_basis : IsTopologicalBasis basis
a : ι
hb : ⊤ ∈ Ioi ↑a
ha : Ioi a = ∅
⊢ IsOpen[generateFrom {s | ∃ a ∈ d, s = Ioi a ∨ s = Iio a}] (Ioi ↑x₁)

Tactic:
· apply isOpen_generateFrom_of_mem
            simp [d]

Goal state after:
Module: Mathlib.MeasureTheory.SetAlgebra

Goal state before:
pp: α : Type u_1
𝒜 : Set (Set α)
s u : Set α
hs✝ : generateSetAlgebra 𝒜 u
A : Set (Set (Set α))
A_fin : A.Finite
mem_A : ∀ a ∈ A, a.Finite
hA : ∀ a ∈ A, ∀ t ∈ a, t ∈ 𝒜 ∨ tᶜ ∈ 𝒜
u_eq : u = ⋃ a ∈ A, ⋂ t ∈ a, t
this✝ : Finite ↑A
this : ∀ (a : ↑A), Finite ↑↑a
x : α
f : (i : Set (Set α)) → i ∈ A → Set α
hf : ∀ (i : Set (Set α)) (i_1 : i ∈ A), f i i_1 ∈ i ∧ x ∉ f i i_1
x✝ : Set α
a : Set (Set α)
ha : a ∈ A
h :
  (↑((fun x_1 ↦
            match x_1 with
            | ⟨a, ha⟩ => ⟨f a ha, ⋯⟩)
          ⟨a, ⋯⟩))ᶜ =
    x✝
⊢ x ∈ x✝

Tactic:
rw [← h]; exact (hf a ha).2

Goal state after:
Module: Mathlib.MeasureTheory.Measure.AddContent

Goal state before:
pp: case h_ss
α : Type u_1
C : Set (Set α)
s t : Set α
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
hs : s ∈ C
ht : t ∈ C
hst : s ⊆ t
⊢ ↑(insert s (hC.disjointOfDiff ht hs)) ⊆ C

pp: case h_dis
α : Type u_1
C : Set (Set α)
s t : Set α
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
hs : s ∈ C
ht : t ∈ C
hst : s ⊆ t
⊢ (↑(insert s (hC.disjointOfDiff ht hs))).PairwiseDisjoint id

pp: case h_mem
α : Type u_1
C : Set (Set α)
s t : Set α
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
hs : s ∈ C
ht : t ∈ C
hst : s ⊆ t
⊢ ⋃₀ ↑(insert s (hC.disjointOfDiff ht hs)) ∈ C

Tactic:
· rw [coe_insert]
    exact Set.insert_subset hs (hC.subset_disjointOfDiff ht hs)

Goal state after:
case h_dis
α : Type u_1
C : Set (Set α)
s t : Set α
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
hs : s ∈ C
ht : t ∈ C
hst : s ⊆ t
⊢ (↑(insert s (hC.disjointOfDiff ht hs))).PairwiseDisjoint id

case h_mem
α : Type u_1
C : Set (Set α)
s t : Set α
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
hs : s ∈ C
ht : t ∈ C
hst : s ⊆ t
⊢ ⋃₀ ↑(insert s (hC.disjointOfDiff ht hs)) ∈ C
Module: Mathlib.MeasureTheory.Measure.AddContent

Goal state before:
pp: α : Type u_1
C : Set (Set α)
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
J J' : Finset (Set α)
hJ : ↑J ⊆ C
hJdisj : (↑J).PairwiseDisjoint id
hJ' : ↑J' ⊆ C
hJ'disj : (↑J').PairwiseDisjoint id
h : ⋃₀ ↑J = ⋃₀ ↑J'
s : Set α
hs : s ∈ J
⊢ m s = ∑ t ∈ J', m (s ∩ t)

Tactic:
have : s = ⋃ t ∈ J', s ∩ t := by
      simp_rw [← Finset.set_biUnion_coe, ← inter_iUnion, left_eq_inter, ← sUnion_eq_biUnion, ← h]
      exact subset_sUnion_of_mem hs

Goal state after:
α : Type u_1
C : Set (Set α)
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
hC : IsSetSemiring C
J J' : Finset (Set α)
hJ : ↑J ⊆ C
hJdisj : (↑J).PairwiseDisjoint id
hJ' : ↑J' ⊆ C
hJ'disj : (↑J').PairwiseDisjoint id
h : ⋃₀ ↑J = ⋃₀ ↑J'
s : Set α
hs : s ∈ J
this : s = ⋃ t ∈ J', s ∩ t
⊢ m s = ∑ t ∈ J', m (s ∩ t)
Module: Mathlib.MeasureTheory.Constructions.ProjectiveFamilyContent

Goal state before:
pp: ι : Type u_1
α : ι → Type u_2
mα : (i : ι) → MeasurableSpace (α i)
P : (J : Finset ι) → Measure ((j : ↥J) → α ↑j)
s t : Set ((i : ι) → α i)
hP : IsProjectiveMeasureFamily P
hs : s ∈ measurableCylinders α
ht : t ∈ measurableCylinders α
hst : Disjoint s t
⊢ projectiveFamilyFun P (s ∪ t) = projectiveFamilyFun P s + projectiveFamilyFun P t

Tactic:
obtain ⟨I, S, hS, hs_eq⟩ := (mem_measurableCylinders _).1 hs
  obtain ⟨J, T, hT, ht_eq⟩ := (mem_measurableCylinders _).1 ht
  classical
  let S' := restrict₂ (subset_union_left (s₂ := J)) ⁻¹' S
  let T' := restrict₂ (subset_union_right (s₁ := I)) ⁻¹' T
  have hS' : MeasurableSet S' := measurable_restrict₂ _ hS
  have hT' : MeasurableSet T' := measurable_restrict₂ _ hT
  have h_eq1 : s = cylinder (I ∪ J) S' := by rw [hs_eq]; exact cylinder_eq_cylinder_union I S J
  have h_eq2 : t = cylinder (I ∪ J) T' := by rw [ht_eq]; exact cylinder_eq_cylinder_union J T I
  have h_eq3 : s ∪ t = cylinder (I ∪ J) (S' ∪ T') := by
    rw [hs_eq, ht_eq]; exact union_cylinder _ _ _ _
  rw [projectiveFamilyFun_congr hP hs h_eq1 hS', projectiveFamilyFun_congr hP ht h_eq2 hT',
    projectiveFamilyFun_congr hP (union_mem_measurableCylinders hs ht) h_eq3 (hS'.union hT')]
  cases isEmpty_or_nonempty (Π i, α i) with
  | inl h => simp [hP.eq_zero_of_isEmpty]
  | inr h =>
    rw [measure_union _ hT']
    rwa [hs_eq, ht_eq, disjoint_cylinder_iff] at hst

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

Goal state before:
pp: case a.inr.coe.coe.refine_2.ht
ι : Type u_1
inst✝¹ : Preorder ι
ts : TopologicalSpace ι
ht : OrderTopology ι
inst✝ : SecondCountableTopology ι
x₀ : ι
c : Set ι
c_count : c.Countable
hc : ts = generateFrom {s | ∃ a ∈ c, s = Ioi a ∨ s = Iio a}
c' : Set ι
c'_count : c'.Countable
hc' : Dense c'
x₁ : ι := ⋯
d : Set (WithTop ι) := ⋯
basis : Set (Set ι) := ⋯
h_basis : IsTopologicalBasis basis
a b : ι
hb✝ : b < a
f g : Set ι
hfc : f ⊆ c
hgc : g ⊆ c
f_fin : f.Finite
g_fin : g.Finite
hb : b ∈ (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a
hfg : (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a ⊆ Iio a
⊢ IsOpen[generateFrom {s | ∃ a ∈ d, s = Ioi a ∨ s = Iio a}] (Iio ⊤)

pp: case a.inr.coe.coe.refine_2.hs
ι : Type u_1
inst✝¹ : Preorder ι
ts : TopologicalSpace ι
ht : OrderTopology ι
inst✝ : SecondCountableTopology ι
x₀ : ι
c : Set ι
c_count : c.Countable
hc : ts = generateFrom {s | ∃ a ∈ c, s = Ioi a ∨ s = Iio a}
c' : Set ι
c'_count : c'.Countable
hc' : Dense c'
x₁ : ι := ⋯
d : Set (WithTop ι) := ⋯
basis : Set (Set ι) := ⋯
h_basis : IsTopologicalBasis basis
a b : ι
hb✝ : b < a
f g : Set ι
hfc : f ⊆ c
hgc : g ⊆ c
f_fin : f.Finite
g_fin : g.Finite
hb : b ∈ (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a
hfg : (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a ⊆ Iio a
⊢ IsOpen[generateFrom {s | ∃ a ∈ d, s = Ioi a ∨ s = Iio a}] ((⋂ z ∈ f, Ioi ↑z) ∩ ⋂ z ∈ g, Iio ↑z)

Tactic:
· apply isOpen_generateFrom_of_mem
            simp [d]

Goal state after:
case a.inr.coe.coe.refine_2.hs
ι : Type u_1
inst✝¹ : Preorder ι
ts : TopologicalSpace ι
ht : OrderTopology ι
inst✝ : SecondCountableTopology ι
x₀ : ι
c : Set ι
c_count : c.Countable
hc : ts = generateFrom {s | ∃ a ∈ c, s = Ioi a ∨ s = Iio a}
c' : Set ι
c'_count : c'.Countable
hc' : Dense c'
x₁ : ι := ⋯
d : Set (WithTop ι) := ⋯
basis : Set (Set ι) := ⋯
h_basis : IsTopologicalBasis basis
a b : ι
hb✝ : b < a
f g : Set ι
hfc : f ⊆ c
hgc : g ⊆ c
f_fin : f.Finite
g_fin : g.Finite
hb : b ∈ (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a
hfg : (⋂ a ∈ f, Ioi a) ∩ ⋂ a ∈ g, Iio a ⊆ Iio a
⊢ IsOpen[generateFrom {s | ∃ a ∈ d, s = Ioi a ∨ s = Iio a}] ((⋂ z ∈ f, Ioi ↑z) ∩ ⋂ z ∈ g, Iio ↑z)
Module: Mathlib.Topology.Order.WithTop

Goal state before:
pp: ι : Type u_1
inst✝³ : LinearOrder ι
inst✝² : TopologicalSpace ι
inst✝¹ : OrderTopology ι
inst✝ : OrderTop ι
h_fr : frontier {⊤} = ∅
⊢ ∀ a ∈ frontier {x | x = ⊤},
    Tendsto (fun x ↦ Sum.inr ()) (𝓝[{x | x = ⊤}] a) (𝓝 (if a = ⊤ then Sum.inr () else Sum.inl a.untopA))

Tactic:
simp [h_fr]

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

Goal state before:
pp: ι : Type u_1
inst✝³ : LinearOrder ι
inst✝² : TopologicalSpace ι
inst✝¹ : OrderTopology ι
inst✝ : OrderTop ι
h_fr : frontier {⊤} = ∅
⊢ ∀ a ∈ frontier {x | x = ⊤},
    Tendsto (fun x ↦ Sum.inl x.untopA) (𝓝[{x | ¬x = ⊤}] a) (𝓝 (if a = ⊤ then Sum.inr () else Sum.inl a.untopA))

Tactic:
simp [h_fr]

Goal state after:
Module: Mathlib.MeasureTheory.Measure.AddContent

Goal state before:
pp: case insert
α : Type u_1
C : Set (Set α)
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
ι : Type u_3
hC : IsSetRing C
s : ι → Set α
i : ι
S : Finset ι
hiS : i ∉ S
h : (∀ n ∈ S, s n ∈ C) → (↑S).PairwiseDisjoint s → m (⋃ i ∈ S, s i) = ∑ i ∈ S, m (s i)
hs : ∀ n ∈ insert i S, s n ∈ C
hS : (↑(insert i S)).PairwiseDisjoint s
⊢ m (⋃ i_1 ∈ ↑(insert i S), s i_1) = m (s i) + ∑ x ∈ S, m (s x)

Tactic:
Finset.coe_insert,

Goal state after:
case insert
α : Type u_1
C : Set (Set α)
G : Type u_2
inst✝ : AddCommMonoid G
m : AddContent G C
ι : Type u_3
hC : IsSetRing C
s : ι → Set α
i : ι
S : Finset ι
hiS : i ∉ S
h : (∀ n ∈ S, s n ∈ C) → (↑S).PairwiseDisjoint s → m (⋃ i ∈ S, s i) = ∑ i ∈ S, m (s i)
hs : ∀ n ∈ insert i S, s n ∈ C
hS : (↑(insert i S)).PairwiseDisjoint s
⊢ m (⋃ i_1 ∈ insert i ↑S, s i_1) = m (s i) + ∑ x ∈ S, m (s x)
Module: Mathlib.MeasureTheory.Measure.AddContent

Goal state before:
pp: case insert
α : Type u_1
C : Set (Set α)
s✝ t : Set α
I✝ : Finset (Set α)
G : Type u_2
inst✝ : AddCommMonoid G
m✝ m' : AddContent G C
m : Set α → G
hC : IsSetRing C
m_empty : m ∅ = 0
m_add : ∀ {s t : Set α}, s ∈ C → t ∈ C → Disjoint s t → m (s ∪ t) = m s + m t
s : Set α
I : Finset (Set α)
hsI : s ∉ I
h : ↑I ⊆ C → (↑I).PairwiseDisjoint id → ⋃₀ ↑I ∈ C → m (⋃₀ ↑I) = ∑ u ∈ I, m u
h_ss : insert s ↑I ⊆ C
h_dis : (insert s ↑I).PairwiseDisjoint id
h_mem : ⋃₀ insert s ↑I ∈ C
⊢ m (⋃₀ insert s ↑I) = ∑ u ∈ insert s I, m u

Tactic:
Set.insert_subset_iff

Goal state after:
case insert
α : Type u_1
C : Set (Set α)
s✝ t : Set α
I✝ : Finset (Set α)
G : Type u_2
inst✝ : AddCommMonoid G
m✝ m' : AddContent G C
m : Set α → G
hC : IsSetRing C
m_empty : m ∅ = 0
m_add : ∀ {s t : Set α}, s ∈ C → t ∈ C → Disjoint s t → m (s ∪ t) = m s + m t
s : Set α
I : Finset (Set α)
hsI : s ∉ I
h : ↑I ⊆ C → (↑I).PairwiseDisjoint id → ⋃₀ ↑I ∈ C → m (⋃₀ ↑I) = ∑ u ∈ I, m u
h_ss : s ∈ C ∧ ↑I ⊆ C
h_dis : (insert s ↑I).PairwiseDisjoint id
h_mem : ⋃₀ insert s ↑I ∈ C
⊢ m (⋃₀ insert s ↑I) = ∑ u ∈ insert s I, m u