mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.GradedAlgebra.HomogeneousLocalization

Goal state before:
pp: case pos.refine_1
ι : Type u_1
A : Type u_2
σ : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : SetLike σ A
inst✝⁴ : AddSubgroupClass σ A
inst✝³ : AddCommMonoid ι
inst✝² : DecidableEq ι
𝒜 : ι → σ
inst✝¹ : GradedRing 𝒜
f : A
d : ι
hf : f ∈ 𝒜 d
ι' : Type u_4
inst✝ : Fintype ι'
v : ι' → A
hx : Algebra.adjoin (↥(𝒜 0)) (Set.range v) = ⊤
dv : ι' → ι
hxd : ∀ (i : ι'), v i ∈ 𝒜 (dv i)
HH : ¬Subsingleton (Away 𝒜 f)
n : ι
a : A
j : ℕ
hb' : (fun x ↦ f ^ x) j ∈ 𝒜 n
hfj : ¬f ^ j = 0
ai : ι' → ℕ
H : ∑ i, ai i • dv i = n
⊢ n = j • d

pp: case pos.refine_2
ι : Type u_1
A : Type u_2
σ : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : SetLike σ A
inst✝⁴ : AddSubgroupClass σ A
inst✝³ : AddCommMonoid ι
inst✝² : DecidableEq ι
𝒜 : ι → σ
inst✝¹ : GradedRing 𝒜
f : A
d : ι
hf : f ∈ 𝒜 d
ι' : Type u_4
inst✝ : Fintype ι'
v : ι' → A
hx : Algebra.adjoin (↥(𝒜 0)) (Set.range v) = ⊤
dv : ι' → ι
hxd : ∀ (i : ι'), v i ∈ 𝒜 (dv i)
HH : ¬Subsingleton (Away 𝒜 f)
n : ι
a : A
j : ℕ
hb' : (fun x ↦ f ^ x) j ∈ 𝒜 n
hfj : ¬f ^ j = 0
ai : ι' → ℕ
H : ∑ i, ai i • dv i = n
⊢ Away.mk 𝒜 hf j (∏ i, v i ^ ai i) ⋯ =
    mk { deg := n, num := ((decompose 𝒜) (∏ i, v i ^ ai i)) n, den := ⟨f ^ j, hb'⟩, den_mem := ⋯ }

Tactic:
· exact DirectSum.degree_eq_of_mem_mem 𝒜 hb'
          (SetLike.pow_mem_graded j hf) hfj

Goal state after:
case pos.refine_2
ι : Type u_1
A : Type u_2
σ : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : SetLike σ A
inst✝⁴ : AddSubgroupClass σ A
inst✝³ : AddCommMonoid ι
inst✝² : DecidableEq ι
𝒜 : ι → σ
inst✝¹ : GradedRing 𝒜
f : A
d : ι
hf : f ∈ 𝒜 d
ι' : Type u_4
inst✝ : Fintype ι'
v : ι' → A
hx : Algebra.adjoin (↥(𝒜 0)) (Set.range v) = ⊤
dv : ι' → ι
hxd : ∀ (i : ι'), v i ∈ 𝒜 (dv i)
HH : ¬Subsingleton (Away 𝒜 f)
n : ι
a : A
j : ℕ
hb' : (fun x ↦ f ^ x) j ∈ 𝒜 n
hfj : ¬f ^ j = 0
ai : ι' → ℕ
H : ∑ i, ai i • dv i = n
⊢ Away.mk 𝒜 hf j (∏ i, v i ^ ai i) ⋯ =
    mk { deg := n, num := ((decompose 𝒜) (∏ i, v i ^ ai i)) n, den := ⟨f ^ j, hb'⟩, den_mem := ⋯ }
Module: Mathlib.AlgebraicGeometry.ProjectiveSpectrum.Functor

Goal state before:
pp: A B σ τ : Type u
inst✝⁷ : CommRing A
inst✝⁶ : SetLike σ A
inst✝⁵ : AddSubgroupClass σ A
inst✝⁴ : CommRing B
inst✝³ : SetLike τ B
inst✝² : AddSubgroupClass τ B
𝒜 : ℕ → σ
ℬ : ℕ → τ
inst✝¹ : GradedRing 𝒜
inst✝ : GradedRing ℬ
f : 𝒜 →+*ᵍ ℬ
hf : ℬ₊ ≤ HomogeneousIdeal.map f (𝒜₊)
i : ℕ
s : A
hs : s ∈ 𝒜 i
n : ℕ
x : A
hx : x ∈ 𝒜 (n • i)
⊢ (CommRingCat.Hom.hom (Scheme.Hom.appLE (map f hf) (basicOpen 𝒜 s) (basicOpen ℬ (f s)) ⋯))
      ((CommRingCat.Hom.hom (awayToSection 𝒜 s)) (Away.mk 𝒜 hs n x hx)) =
    (CommRingCat.Hom.hom (awayToSection ℬ (f s))) (Away.mk ℬ ⋯ n (f x) ⋯)

Tactic:
refine Subtype.ext <| funext fun p ↦ ?_

Goal state after:
A B σ τ : Type u
inst✝⁷ : CommRing A
inst✝⁶ : SetLike σ A
inst✝⁵ : AddSubgroupClass σ A
inst✝⁴ : CommRing B
inst✝³ : SetLike τ B
inst✝² : AddSubgroupClass τ B
𝒜 : ℕ → σ
ℬ : ℕ → τ
inst✝¹ : GradedRing 𝒜
inst✝ : GradedRing ℬ
f : 𝒜 →+*ᵍ ℬ
hf : ℬ₊ ≤ HomogeneousIdeal.map f (𝒜₊)
i : ℕ
s : A
hs : s ∈ 𝒜 i
n : ℕ
x : A
hx : x ∈ 𝒜 (n • i)
p : ↥(Opposite.unop (Opposite.op (basicOpen ℬ (f s))))
⊢ ↑((CommRingCat.Hom.hom (Scheme.Hom.appLE (map f hf) (basicOpen 𝒜 s) (basicOpen ℬ (f s)) ⋯))
          ((CommRingCat.Hom.hom (awayToSection 𝒜 s)) (Away.mk 𝒜 hs n x hx)))
      p =
    ↑((CommRingCat.Hom.hom (awayToSection ℬ (f s))) (Away.mk ℬ ⋯ n (f x) ⋯)) p
Module: Mathlib.AlgebraicGeometry.Modules.Tilde

Goal state before:
pp: case refine_2
X : Scheme
M : X.Modules
inst✝ : SheafOfModules.IsQuasicoherent M
I : Type u
W : I → TopologicalSpace.Opens ↥X
cov : (Opens.grothendieckTopology ↥X).CoversTop W
pres : (i : I) → (SheafOfModules.over M (W i)).Presentation
κ : I → Set (TopologicalSpace.Opens ↥X)
hsub : ∀ (i : I), κ i ⊆ X.affineOpens
heq : ∀ (i : I), W i = sSup (κ i)
⊢ IsOpenCover fun j ↦ ↑j.snd

pp: case refine_3
X : Scheme
M : X.Modules
inst✝ : SheafOfModules.IsQuasicoherent M
I : Type u
W : I → TopologicalSpace.Opens ↥X
cov : (Opens.grothendieckTopology ↥X).CoversTop W
pres : (i : I) → (SheafOfModules.over M (W i)).Presentation
κ : I → Set (TopologicalSpace.Opens ↥X)
hsub : ∀ (i : I), κ i ⊆ X.affineOpens
heq : ∀ (i : I), W i = sSup (κ i)
⊢ ∀ (i : (i : I) × ↑(κ i)), IsAffineOpen ((fun j ↦ ↑j.snd) i)

Tactic:
· rw [Opens.coversTop_iff, IsOpenCover] at cov
    rw [IsOpenCover, iSup_sigma, ← cov]
    refine iSup_congr fun i ↦ ?_
    rw [heq i, sSup_eq_iSup']

Goal state after:
case refine_3
X : Scheme
M : X.Modules
inst✝ : SheafOfModules.IsQuasicoherent M
I : Type u
W : I → TopologicalSpace.Opens ↥X
cov : (Opens.grothendieckTopology ↥X).CoversTop W
pres : (i : I) → (SheafOfModules.over M (W i)).Presentation
κ : I → Set (TopologicalSpace.Opens ↥X)
hsub : ∀ (i : I), κ i ⊆ X.affineOpens
heq : ∀ (i : I), W i = sSup (κ i)
⊢ ∀ (i : (i : I) × ↑(κ i)), IsAffineOpen ((fun j ↦ ↑j.snd) i)
Module: Mathlib.AlgebraicGeometry.ValuativeCriterion

Goal state before:
pp: X Y : Scheme
f : X ⟶ Y
R : Type u
commRing✝ : CommRing R
domain✝ : IsDomain R
valuationRing✝ : ValuationRing R
K : Type u
field✝ : Field K
algebra✝ : Algebra R K
isFractionRing✝ : IsFractionRing R K
i₁ : Spec (CommRingCat.of K) ⟶ X
i₂ : Spec (CommRingCat.of R) ⟶ Y
w : i₁ ≫ f = Spec.map (CommRingCat.ofHom (algebraMap R K)) ≫ i₂
this✝¹ : IsDomain ↑(CommRingCat.of R)
this✝ : ValuationRing ↑(CommRingCat.of R)
this : Field ↑(CommRingCat.of K) := field✝
H : topologically (@SpecializingMap) (pullback.fst i₂ f)
lft : Spec (CommRingCat.of K) ⟶ pullback i₂ f := pullback.lift (Spec.map (CommRingCat.ofHom (algebraMap R K))) i₁ ⋯
x : ↥(pullback i₂ f)
h₁ : flip (fun x1 x2 ↦ x1 ⤳ x2) x (lft (closedPoint ↑(CommRingCat.of K)))
h₂ : (pullback.fst i₂ f) x = closedPoint R
e : CommRingCat.of R ≅ (Spec (CommRingCat.of R)).presheaf.stalk ((pullback.fst i₂ f) x) :=
  (stalkClosedPointIso (CommRingCat.of R)).symm ≪≫ (Spec (CommRingCat.of R)).presheaf.stalkCongr ⋯
⊢ ⋯.HasLift

Tactic:
let α := e.hom ≫ (pullback.fst i₂ f).stalkMap x

Goal state after:
X Y : Scheme
f : X ⟶ Y
R : Type u
commRing✝ : CommRing R
domain✝ : IsDomain R
valuationRing✝ : ValuationRing R
K : Type u
field✝ : Field K
algebra✝ : Algebra R K
isFractionRing✝ : IsFractionRing R K
i₁ : Spec (CommRingCat.of K) ⟶ X
i₂ : Spec (CommRingCat.of R) ⟶ Y
w : i₁ ≫ f = Spec.map (CommRingCat.ofHom (algebraMap R K)) ≫ i₂
this✝¹ : IsDomain ↑(CommRingCat.of R)
this✝ : ValuationRing ↑(CommRingCat.of R)
this : Field ↑(CommRingCat.of K) := field✝
H : topologically (@SpecializingMap) (pullback.fst i₂ f)
lft : Spec (CommRingCat.of K) ⟶ pullback i₂ f := pullback.lift (Spec.map (CommRingCat.ofHom (algebraMap R K))) i₁ ⋯
x : ↥(pullback i₂ f)
h₁ : flip (fun x1 x2 ↦ x1 ⤳ x2) x (lft (closedPoint ↑(CommRingCat.of K)))
h₂ : (pullback.fst i₂ f) x = closedPoint R
e : CommRingCat.of R ≅ (Spec (CommRingCat.of R)).presheaf.stalk ((pullback.fst i₂ f) x) :=
  (stalkClosedPointIso (CommRingCat.of R)).symm ≪≫ (Spec (CommRingCat.of R)).presheaf.stalkCongr ⋯
α : CommRingCat.of R ⟶ (pullback i₂ f).presheaf.stalk x := e.hom ≫ Scheme.Hom.stalkMap (pullback.fst i₂ f) x
⊢ ⋯.HasLift
Module: Mathlib.AlgebraicGeometry.ProjectiveSpectrum.Scheme

Goal state before:
pp: case surj.refine_2
A : Type u_1
σ : Type u_2
inst✝³ : CommRing A
inst✝² : SetLike σ A
inst✝¹ : AddSubgroupClass σ A
𝒜 : ℕ → σ
inst✝ : GradedRing 𝒜
f : A
x : ↥(pbo f)
m : ℕ
f_deg : f ∈ 𝒜 m
hm : 0 < m
this : Algebra (A⁰_ f) (AtPrime 𝒜 (↑x).asHomogeneousIdeal.toIdeal) := (mapId 𝒜 ⋯).toAlgebra
i : ℕ
a : ↥(𝒜 i)
b : A
hb : b ∈ 𝒜 i
hb' : b ∉ (↑x).asHomogeneousIdeal
⊢ (algebraMap A (Localization (↑x).asHomogeneousIdeal.toIdeal.primeCompl)) (f ^ i * (↑a * b ^ m)) =
    (algebraMap A (Localization (↑x).asHomogeneousIdeal.toIdeal.primeCompl)) (b * f ^ i * (↑a * b ^ (m - 1)))

Tactic:
mul_comm b,

Goal state after:
case surj.refine_2
A : Type u_1
σ : Type u_2
inst✝³ : CommRing A
inst✝² : SetLike σ A
inst✝¹ : AddSubgroupClass σ A
𝒜 : ℕ → σ
inst✝ : GradedRing 𝒜
f : A
x : ↥(pbo f)
m : ℕ
f_deg : f ∈ 𝒜 m
hm : 0 < m
this : Algebra (A⁰_ f) (AtPrime 𝒜 (↑x).asHomogeneousIdeal.toIdeal) := (mapId 𝒜 ⋯).toAlgebra
i : ℕ
a : ↥(𝒜 i)
b : A
hb : b ∈ 𝒜 i
hb' : b ∉ (↑x).asHomogeneousIdeal
⊢ (algebraMap A (Localization (↑x).asHomogeneousIdeal.toIdeal.primeCompl)) (f ^ i * (↑a * b ^ m)) =
    (algebraMap A (Localization (↑x).asHomogeneousIdeal.toIdeal.primeCompl)) (f ^ i * b * (↑a * b ^ (m - 1)))
Module: Mathlib.AlgebraicGeometry.Modules.Tilde

Goal state before:
pp: case h.refine_1
R : CommRingCat
M : (Spec R).Modules
V : (Spec R).Opens
ι : Type u_1
inst✝ : Finite ι
g : ι → ↑R
hg : V = ⨆ i, basicOpen (g i)
h₁ : ∀ (i : ι), Aux M (basicOpen (g i))
h₂ : ∀ (i j : ι), Aux M (basicOpen (g i * g j))
hgle : ∀ (i : ι), basicOpen (g i) ≤ V
hug : ∀ (i : ι) (m : ℕ), IsUnit ((algebraMap (↑R) (Module.End ↑R ↑Γ(M, basicOpen (g i)))) (g i ^ m))
f : ↑R
hf : basicOpen f ≤ V
s : ↑Γ(M, basicOpen f)
hfgi : ∀ (i : ι), basicOpen (f * g i) ≤ basicOpen (g i)
s' : (i : ι) → ↑Γ(M, basicOpen (f * g i)) := fun i ↦ (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) s
N : ℕ
t : (i : ι) → ↑Γ(M, basicOpen (g i))
ht : ∀ (i : ι), f ^ N • s' i = (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) (t i)
K : ℕ
hK :
  ∀ (i j : ι),
    (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) (f ^ K • t i) =
      (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) (f ^ K • t j)
a : ToType ({ obj := M.presheaf, property := ⋯ }.obj.obj (op V))
ha : ∀ (i : ι), (ConcreteCategory.hom ({ obj := M.presheaf, property := ⋯ }.obj.map (homOfLE ⋯).op)) a = f ^ K • t i
⊢ ⨆ i, basicOpen f ⊓ basicOpen (g i) ≤ ⨆ i, basicOpen (f * g i)

Tactic:
basicOpen_mul

Goal state after:
case h.refine_1
R : CommRingCat
M : (Spec R).Modules
V : (Spec R).Opens
ι : Type u_1
inst✝ : Finite ι
g : ι → ↑R
hg : V = ⨆ i, basicOpen (g i)
h₁ : ∀ (i : ι), Aux M (basicOpen (g i))
h₂ : ∀ (i j : ι), Aux M (basicOpen (g i * g j))
hgle : ∀ (i : ι), basicOpen (g i) ≤ V
hug : ∀ (i : ι) (m : ℕ), IsUnit ((algebraMap (↑R) (Module.End ↑R ↑Γ(M, basicOpen (g i)))) (g i ^ m))
f : ↑R
hf : basicOpen f ≤ V
s : ↑Γ(M, basicOpen f)
hfgi : ∀ (i : ι), basicOpen (f * g i) ≤ basicOpen (g i)
s' : (i : ι) → ↑Γ(M, basicOpen (f * g i)) := fun i ↦ (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) s
N : ℕ
t : (i : ι) → ↑Γ(M, basicOpen (g i))
ht : ∀ (i : ι), f ^ N • s' i = (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) (t i)
K : ℕ
hK :
  ∀ (i j : ι),
    (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) (f ^ K • t i) =
      (ConcreteCategory.hom (M.presheaf.map (homOfLE ⋯).op)) (f ^ K • t j)
a : ToType ({ obj := M.presheaf, property := ⋯ }.obj.obj (op V))
ha : ∀ (i : ι), (ConcreteCategory.hom ({ obj := M.presheaf, property := ⋯ }.obj.map (homOfLE ⋯).op)) a = f ^ K • t i
⊢ ⨆ i, basicOpen f ⊓ basicOpen (g i) ≤ ⨆ i, basicOpen f ⊓ basicOpen (g i)
Module: Mathlib.AlgebraicGeometry.ValuativeCriterion

Goal state before:
pp: X Y : Scheme
f : X ⟶ Y
inst✝ : IsSeparated f
S : ValuativeCommSq f
l₁ : Spec (CommRingCat.of S.R) ⟶ X
hl₁ : Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)) ≫ l₁ = S.i₁
hl₁' : l₁ ≫ f = S.i₂
l₂ : Spec (CommRingCat.of S.R) ⟶ X
hl₂ : Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)) ≫ l₂ = S.i₁
hl₂' : l₂ ≫ f = S.i₂
h : l₁ ≫ f = l₂ ≫ f
Z : Scheme := pullback (pullback.diagonal f) (pullback.lift l₁ l₂ h)
g : Z ⟶ Spec (CommRingCat.of S.R) := pullback.snd (pullback.diagonal f) (pullback.lift l₁ l₂ h)
this : IsClosedImmersion g
hZ : IsAffine Z
l : Spec (CommRingCat.of S.K) ⟶ Z := pullback.lift S.i₁ (Spec.map (CommRingCat.ofHom (algebraMap S.R S.K))) ⋯
hg : l ≫ g = Spec.map (CommRingCat.ofHom (algebraMap S.R S.K))
e : Arrow.mk (CommRingCat.ofHom (algebraMap S.R S.K)) ≅
  Arrow.mk (Scheme.Hom.appTop (Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)))) :=
  arrowIsoΓSpecOfIsAffine (CommRingCat.ofHom (algebraMap S.R S.K))
P : MorphismProperty CommRingCat :=
  RingHom.toMorphismProperty fun {R S} [CommRing R] [CommRing S] f ↦ Function.Injective ⇑f
⊢ Function.Injective ⇑(ConcreteCategory.hom (Scheme.Hom.appTop (Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)))))

Tactic:
have : (RingHom.toMorphismProperty <| fun f ↦ Function.Injective f).RespectsIso :=
        RingHom.toMorphismProperty_respectsIso_iff.mp RingHom.injective_respectsIso

Goal state after:
X Y : Scheme
f : X ⟶ Y
inst✝ : IsSeparated f
S : ValuativeCommSq f
l₁ : Spec (CommRingCat.of S.R) ⟶ X
hl₁ : Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)) ≫ l₁ = S.i₁
hl₁' : l₁ ≫ f = S.i₂
l₂ : Spec (CommRingCat.of S.R) ⟶ X
hl₂ : Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)) ≫ l₂ = S.i₁
hl₂' : l₂ ≫ f = S.i₂
h : l₁ ≫ f = l₂ ≫ f
Z : Scheme := pullback (pullback.diagonal f) (pullback.lift l₁ l₂ h)
g : Z ⟶ Spec (CommRingCat.of S.R) := pullback.snd (pullback.diagonal f) (pullback.lift l₁ l₂ h)
this✝ : IsClosedImmersion g
hZ : IsAffine Z
l : Spec (CommRingCat.of S.K) ⟶ Z := pullback.lift S.i₁ (Spec.map (CommRingCat.ofHom (algebraMap S.R S.K))) ⋯
hg : l ≫ g = Spec.map (CommRingCat.ofHom (algebraMap S.R S.K))
e : Arrow.mk (CommRingCat.ofHom (algebraMap S.R S.K)) ≅
  Arrow.mk (Scheme.Hom.appTop (Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)))) :=
  arrowIsoΓSpecOfIsAffine (CommRingCat.ofHom (algebraMap S.R S.K))
P : MorphismProperty CommRingCat :=
  RingHom.toMorphismProperty fun {R S} [CommRing R] [CommRing S] f ↦ Function.Injective ⇑f
this : (RingHom.toMorphismProperty fun {R S} [CommRing R] [CommRing S] f ↦ Function.Injective ⇑f).RespectsIso
⊢ Function.Injective ⇑(ConcreteCategory.hom (Scheme.Hom.appTop (Spec.map (CommRingCat.ofHom (algebraMap S.R S.K)))))
Module: Mathlib.AlgebraicGeometry.ProjectiveSpectrum.Proper

Goal state before:
pp: σ : Type u_1
A : Type u_2
inst✝⁴ : CommRing A
inst✝³ : SetLike σ A
inst✝² : AddSubgroupClass σ A
𝒜 : ℕ → σ
inst✝¹ : GradedRing 𝒜
inst✝ : Algebra.FiniteType (↥(𝒜 0)) A
x : Finset A
hx : Algebra.adjoin ↥(𝒜 0) ↑x = ⊤
d : (i : A) → i ∈ x → ℕ
hd : ∀ (i : A) (a : i ∈ x), d i a ≠ 0
hxd : ∀ (i : A) (a : i ∈ x), i ∈ 𝒜 (d i a)
H : ∀ (i : ↥x), IsCompact (basicOpen 𝒜 ↑i).carrier
this : ⋃ i, ↑(basicOpen 𝒜 ↑i) = Set.univ
⊢ IsCompact (⋃ i, ↑(basicOpen 𝒜 ↑i))

Tactic:
exact isCompact_iUnion H

Goal state after:
Module: Mathlib.CategoryTheory.Sites.DenseSubsite.OneHypercoverDense

Goal state before:
pp: case refine_1
C₀ : Type u₀
C : Type u
inst✝² : Category.{v₀, u₀} C₀
inst✝¹ : Category.{v, u} C
F : C₀ ⥤ C
J₀ : GrothendieckTopology C₀
J : GrothendieckTopology C
inst✝ : IsDenseSubsite J₀ J F
X : C
data : F.OneHypercoverDenseData J₀ J X
X₀ : C₀
f : F.obj X₀ ⟶ X
this✝ : F.IsCoverDense J
this : F.IsLocallyFull J
R : ⦃W : C⦄ → ⦃p : W ⟶ F.obj X₀⦄ → (Sieve.pullback f data.toOneHypercover.sieve₀).arrows p → Sieve W :=
  fun W p hp ↦
    Sieve.bind (Sieve.coverByImage F W).arrows fun U π hπ ↦
      Sieve.pullback (Nonempty.some hπ).lift (Sieve.functorPushforward F (F.imageSieve ((Nonempty.some hπ).map ≫ p)))
⊢ Sieve.bind (Sieve.pullback f data.toOneHypercover.sieve₀).arrows R ≤ Sieve.functorPushforward F (data.sieve f)

pp: case refine_2
C₀ : Type u₀
C : Type u
inst✝² : Category.{v₀, u₀} C₀
inst✝¹ : Category.{v, u} C
F : C₀ ⥤ C
J₀ : GrothendieckTopology C₀
J : GrothendieckTopology C
inst✝ : IsDenseSubsite J₀ J F
X : C
data : F.OneHypercoverDenseData J₀ J X
X₀ : C₀
f : F.obj X₀ ⟶ X
this✝ : F.IsCoverDense J
this : F.IsLocallyFull J
R : ⦃W : C⦄ → ⦃p : W ⟶ F.obj X₀⦄ → (Sieve.pullback f data.toOneHypercover.sieve₀).arrows p → Sieve W :=
  fun W p hp ↦
    Sieve.bind (Sieve.coverByImage F W).arrows fun U π hπ ↦
      Sieve.pullback (Nonempty.some hπ).lift (Sieve.functorPushforward F (F.imageSieve ((Nonempty.some hπ).map ≫ p)))
W : C
p : W ⟶ F.obj X₀
hp : (Sieve.pullback f data.toOneHypercover.sieve₀).arrows p
⊢ ∀ ⦃Y : C⦄ ⦃f : Y ⟶ W⦄ (H : (Sieve.coverByImage F W).arrows f),
    Sieve.pullback (Nonempty.some H).lift (Sieve.functorPushforward F (F.imageSieve ((Nonempty.some H).map ≫ p))) ∈ J Y

Tactic:
· rintro W' _ ⟨W, _, p, hp, ⟨Y₀, a, b, hb, ⟨U, c, d, ⟨x₁, w₁⟩, fac⟩, rfl⟩, rfl⟩
    have hp' := Sieve.ofArrows.fac hp
    dsimp at hp'
    refine ⟨U, x₁, d, ⟨Sieve.ofArrows.i hp,
      F.map c ≫ (Nonempty.some hb).map ≫ Sieve.ofArrows.h hp, ?_⟩, ?_⟩
    · rw [w₁, assoc, assoc, assoc, assoc, hp']
    · rw [w₁, assoc, ← reassoc_of% fac, hb.some.fac_assoc]

Goal state after:
case refine_2
C₀ : Type u₀
C : Type u
inst✝² : Category.{v₀, u₀} C₀
inst✝¹ : Category.{v, u} C
F : C₀ ⥤ C
J₀ : GrothendieckTopology C₀
J : GrothendieckTopology C
inst✝ : IsDenseSubsite J₀ J F
X : C
data : F.OneHypercoverDenseData J₀ J X
X₀ : C₀
f : F.obj X₀ ⟶ X
this✝ : F.IsCoverDense J
this : F.IsLocallyFull J
R : ⦃W : C⦄ → ⦃p : W ⟶ F.obj X₀⦄ → (Sieve.pullback f data.toOneHypercover.sieve₀).arrows p → Sieve W :=
  fun W p hp ↦
    Sieve.bind (Sieve.coverByImage F W).arrows fun U π hπ ↦
      Sieve.pullback (Nonempty.some hπ).lift (Sieve.functorPushforward F (F.imageSieve ((Nonempty.some hπ).map ≫ p)))
W : C
p : W ⟶ F.obj X₀
hp : (Sieve.pullback f data.toOneHypercover.sieve₀).arrows p
⊢ ∀ ⦃Y : C⦄ ⦃f : Y ⟶ W⦄ (H : (Sieve.coverByImage F W).arrows f),
    Sieve.pullback (Nonempty.some H).lift (Sieve.functorPushforward F (F.imageSieve ((Nonempty.some H).map ≫ p))) ∈ J Y
Module: Mathlib.CategoryTheory.Sites.Hypercover.ZeroFamily

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
P : PreZeroHypercoverFamily C
h :
  ∀ {X : C} (E : PreZeroHypercover X) (F : (i : E.I₀) → PreZeroHypercover (E.X i)),
    P.property E → (∀ (i : E.I₀), P.property (F i)) → P.property (E.bind F)
ι : Type (max u v)
S : C
X : ι → C
f : (i : ι) → X i ⟶ S
hf : Presieve.ofArrows X f ∈ P.precoverage.coverings S
σ : ι → Type (max u v)
Y : (i : ι) → σ i → C
g : (i : ι) → (j : σ i) → Y i j ⟶ X i
hg : ∀ (i : ι), Presieve.ofArrows (Y i) (g i) ∈ P.precoverage.coverings (X i)
E : PreZeroHypercover S := { I₀ := ι, X := X, f := f }
⊢ (Presieve.ofArrows (fun p ↦ Y p.fst p.snd) fun x ↦ g x.fst x.snd ≫ f x.fst) ∈ P.precoverage.coverings S

Tactic:
let F (i : ι) : PreZeroHypercover (E.X i) := ⟨_, _, g i⟩

Goal state after:
C : Type u
inst✝ : Category.{v, u} C
P : PreZeroHypercoverFamily C
h :
  ∀ {X : C} (E : PreZeroHypercover X) (F : (i : E.I₀) → PreZeroHypercover (E.X i)),
    P.property E → (∀ (i : E.I₀), P.property (F i)) → P.property (E.bind F)
ι : Type (max u v)
S : C
X : ι → C
f : (i : ι) → X i ⟶ S
hf : Presieve.ofArrows X f ∈ P.precoverage.coverings S
σ : ι → Type (max u v)
Y : (i : ι) → σ i → C
g : (i : ι) → (j : σ i) → Y i j ⟶ X i
hg : ∀ (i : ι), Presieve.ofArrows (Y i) (g i) ∈ P.precoverage.coverings (X i)
E : PreZeroHypercover S := { I₀ := ι, X := X, f := f }
F : (i : ι) → PreZeroHypercover (E.X i) := fun i ↦ { I₀ := σ i, X := Y i, f := g i }
⊢ (Presieve.ofArrows (fun p ↦ Y p.fst p.snd) fun x ↦ g x.fst x.snd ≫ f x.fst) ∈ P.precoverage.coverings S
Module: Mathlib.CategoryTheory.Sites.EffectiveEpimorphic

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
X Y : C
f : Y ⟶ X
Hf : IsColimit (Sieve.generateSingleton f).arrows.cocone
aux : {W : C} →
  (e : Y ⟶ W) →
    (∀ {Z : C} (g₁ g₂ : Z ⟶ Y), g₁ ≫ f = g₂ ≫ f → g₁ ≫ e = g₂ ≫ e) →
      Cocone (Sieve.generateSingleton f).arrows.diagram :=
  fun {W} e h ↦
    { pt := W,
      ι :=
        {
          app := fun x ↦
            match x with
            | { obj := obj, property := hT } => Exists.choose hT ≫ e,
          naturality := ⋯ } }
W : C
e : Y ⟶ W
h : ∀ {Z : C} (g₁ g₂ : Z ⟶ Y), g₁ ≫ f = g₂ ≫ f → g₁ ≫ e = g₂ ≫ e
this : f ≫ Hf.desc { pt := W, ι := { app := fun x ↦ Exists.choose ⋯ ≫ e, naturality := ⋯ } } = Exists.choose ⋯ ≫ e
⊢ Exists.choose ⋯ ≫ e = e

Tactic:
clear this

Goal state after:
C : Type u
inst✝ : Category.{v, u} C
X Y : C
f : Y ⟶ X
Hf : IsColimit (Sieve.generateSingleton f).arrows.cocone
aux : {W : C} →
  (e : Y ⟶ W) →
    (∀ {Z : C} (g₁ g₂ : Z ⟶ Y), g₁ ≫ f = g₂ ≫ f → g₁ ≫ e = g₂ ≫ e) →
      Cocone (Sieve.generateSingleton f).arrows.diagram :=
  fun {W} e h ↦
    { pt := W,
      ι :=
        {
          app := fun x ↦
            match x with
            | { obj := obj, property := hT } => Exists.choose hT ≫ e,
          naturality := ⋯ } }
W : C
e : Y ⟶ W
h : ∀ {Z : C} (g₁ g₂ : Z ⟶ Y), g₁ ≫ f = g₂ ≫ f → g₁ ≫ e = g₂ ≫ e
⊢ Exists.choose ⋯ ≫ e = e
Module: Mathlib.CategoryTheory.Sites.DenseSubsite.OneHypercoverDense

Goal state before:
pp: C₀ : Type u₀
C : Type u
inst✝⁴ : Category.{v₀, u₀} C₀
inst✝³ : Category.{v, u} C
F : C₀ ⥤ C
J₀ : GrothendieckTopology C₀
J : GrothendieckTopology C
A : Type u'
inst✝² : Category.{v', u'} A
inst✝¹ : IsDenseSubsite J₀ J F
data : (X : C) → F.OneHypercoverDenseData J₀ J X
inst✝ : HasLimitsOfSize.{w, w, v', u'} A
G₀ : Sheaf J₀ A
X Y : C
X₀ : C₀
f : F.obj X₀ ⟶ X
g : X ⟶ Y
U₀ Y₀ : C₀
c : U₀ ⟶ Y₀
d : Y₀ ⟶ X₀
hd : Presieve.functorPullback F (Sieve.pullback f (data X).toPreOneHypercover.sieve₀).arrows d
hc :
  Presieve.functorPullback F
    (Sieve.pullback (Sieve.ofArrows.h hd ≫ (data X).f (Sieve.ofArrows.i hd) ≫ g)
        (data Y).toPreOneHypercover.sieve₀).arrows
    c
hc' :
  Sieve.ofArrows.h hc ≫ (data Y).f (Sieve.ofArrows.i hc) =
    F.map c ≫ Sieve.ofArrows.h hd ≫ (data X).f (Sieve.ofArrows.i hd) ≫ g
hd' : Sieve.ofArrows.h hd ≫ (data X).f (Sieve.ofArrows.i hd) = F.map d ≫ f
this : F.imageSieve (Sieve.ofArrows.h hc) ⊓ Sieve.pullback c (F.imageSieve (Sieve.ofArrows.h hd)) ∈ J₀ U₀
V₀ : C₀
a : V₀ ⟶ U₀
x₁ : V₀ ⟶ (data Y).X (Sieve.ofArrows.i hc)
fac₁ : F.map x₁ = F.map a ≫ Sieve.ofArrows.h hc
x₂ : V₀ ⟶ (data X).X (Sieve.ofArrows.i hd)
fac₂ : F.map x₂ = F.map (a ≫ c) ≫ Sieve.ofArrows.h hd
⊢ restriction data G₀ ((data X).f (Sieve.ofArrows.i hd) ≫ g) ≫
      IsDenseSubsite.mapPreimage J F G₀ (F.map c ≫ Sieve.ofArrows.h hd) ≫ G₀.obj.map a.op =
    presheafObjπ data G₀ Y (Sieve.ofArrows.i hc) ≫
      IsDenseSubsite.mapPreimage J F G₀ (Sieve.ofArrows.h hc) ≫ G₀.obj.map a.op

Tactic:
IsDenseSubsite.mapPreimage_map_of_fac J F G₀ _ _ x₂ (by simpa using fac₂.symm),

Goal state after:
C₀ : Type u₀
C : Type u
inst✝⁴ : Category.{v₀, u₀} C₀
inst✝³ : Category.{v, u} C
F : C₀ ⥤ C
J₀ : GrothendieckTopology C₀
J : GrothendieckTopology C
A : Type u'
inst✝² : Category.{v', u'} A
inst✝¹ : IsDenseSubsite J₀ J F
data : (X : C) → F.OneHypercoverDenseData J₀ J X
inst✝ : HasLimitsOfSize.{w, w, v', u'} A
G₀ : Sheaf J₀ A
X Y : C
X₀ : C₀
f : F.obj X₀ ⟶ X
g : X ⟶ Y
U₀ Y₀ : C₀
c : U₀ ⟶ Y₀
d : Y₀ ⟶ X₀
hd : Presieve.functorPullback F (Sieve.pullback f (data X).toPreOneHypercover.sieve₀).arrows d
hc :
  Presieve.functorPullback F
    (Sieve.pullback (Sieve.ofArrows.h hd ≫ (data X).f (Sieve.ofArrows.i hd) ≫ g)
        (data Y).toPreOneHypercover.sieve₀).arrows
    c
hc' :
  Sieve.ofArrows.h hc ≫ (data Y).f (Sieve.ofArrows.i hc) =
    F.map c ≫ Sieve.ofArrows.h hd ≫ (data X).f (Sieve.ofArrows.i hd) ≫ g
hd' : Sieve.ofArrows.h hd ≫ (data X).f (Sieve.ofArrows.i hd) = F.map d ≫ f
this : F.imageSieve (Sieve.ofArrows.h hc) ⊓ Sieve.pullback c (F.imageSieve (Sieve.ofArrows.h hd)) ∈ J₀ U₀
V₀ : C₀
a : V₀ ⟶ U₀
x₁ : V₀ ⟶ (data Y).X (Sieve.ofArrows.i hc)
fac₁ : F.map x₁ = F.map a ≫ Sieve.ofArrows.h hc
x₂ : V₀ ⟶ (data X).X (Sieve.ofArrows.i hd)
fac₂ : F.map x₂ = F.map (a ≫ c) ≫ Sieve.ofArrows.h hd
⊢ restriction data G₀ ((data X).f (Sieve.ofArrows.i hd) ≫ g) ≫ G₀.obj.map x₂.op =
    presheafObjπ data G₀ Y (Sieve.ofArrows.i hc) ≫
      IsDenseSubsite.mapPreimage J F G₀ (Sieve.ofArrows.h hc) ≫ G₀.obj.map a.op