mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.CategoryTheory.Monoidal.DayConvolution

Goal state before:
pp: C : Type u₁
inst✝⁷ : Category.{v₁, u₁} C
V : Type u₂
inst✝⁶ : Category.{v₂, u₂} V
inst✝⁵ : MonoidalCategory C
inst✝⁴ : MonoidalCategory V
D : Type u₃
inst✝³ : Category.{v₃, u₃} D
inst✝² : MonoidalCategoryStruct D
inst✝¹ : LawfulDayConvolutionMonoidalCategoryStruct C V D
d : D
inst✝ :
  ∀ (v : V) (d : C), Limits.PreservesColimitsOfShape (CostructuredArrow (Functor.fromPUnit (𝟙_ C)) d) (tensorRight v)
fst✝ : Discrete PUnit.{1}
x : C
⊢ ((((ι C V D).obj (𝟙_ D) ⊠ (ι C V D).obj d).homEquivOfIsLeftKanExtension
            (ExternalProduct.extensionUnitLeft ((ι C V D).obj (𝟙_ D)) (φ ((ι C V D).obj (𝟙_ D))) ((ι C V D).obj d))
            (tensor C ⋙ (ι C V D).obj d))
          ((((ι C V D).obj (𝟙_ D) ⊛ (ι C V D).obj d).homEquivOfIsLeftKanExtension
              (DayConvolution.unit ((ι C V D).obj (𝟙_ D)) ((ι C V D).obj d)) ((ι C V D).obj d))
            ((ι C V D).map (λ_ d).hom))).app
      (fst✝, x) =
    ((((ι C V D).obj (𝟙_ D) ⊠ (ι C V D).obj d).homEquivOfIsLeftKanExtension
            (ExternalProduct.extensionUnitLeft ((ι C V D).obj (𝟙_ D)) (φ ((ι C V D).obj (𝟙_ D))) ((ι C V D).obj d))
            (tensor C ⋙ (ι C V D).obj d))
          ((((ι C V D).obj (𝟙_ D) ⊛ (ι C V D).obj d).homEquivOfIsLeftKanExtension
              (DayConvolution.unit ((ι C V D).obj (𝟙_ D)) ((ι C V D).obj d)) ((ι C V D).obj d))
            (DayConvolutionUnit.leftUnitor ((ι C V D).obj (𝟙_ D)) ((ι C V D).obj d)).hom)).app
      (fst✝, x)

Tactic:
dsimp [corepresentableByLeft]

Goal state after:
C : Type u₁
inst✝⁷ : Category.{v₁, u₁} C
V : Type u₂
inst✝⁶ : Category.{v₂, u₂} V
inst✝⁵ : MonoidalCategory C
inst✝⁴ : MonoidalCategory V
D : Type u₃
inst✝³ : Category.{v₃, u₃} D
inst✝² : MonoidalCategoryStruct D
inst✝¹ : LawfulDayConvolutionMonoidalCategoryStruct C V D
d : D
inst✝ :
  ∀ (v : V) (d : C), Limits.PreservesColimitsOfShape (CostructuredArrow (Functor.fromPUnit (𝟙_ C)) d) (tensorRight v)
fst✝ : Discrete PUnit.{1}
x : C
⊢ (can ▷ ((ι C V D).obj d).obj x ≫ ((ι C V D).obj (𝟙_ D)).obj (𝟙_ C) ◁ 𝟙 (((ι C V D).obj d).obj x)) ≫
      (DayConvolution.unit ((ι C V D).obj (𝟙_ D)) ((ι C V D).obj d)).app (𝟙_ C, x) ≫
        ((ι C V D).map (λ_ d).hom).app (𝟙_ C ⊗ x) =
    (can ▷ ((ι C V D).obj d).obj x ≫ ((ι C V D).obj (𝟙_ D)).obj (𝟙_ C) ◁ 𝟙 (((ι C V D).obj d).obj x)) ≫
      (DayConvolution.unit ((ι C V D).obj (𝟙_ D)) ((ι C V D).obj d)).app (𝟙_ C, x) ≫
        (DayConvolutionUnit.leftUnitor ((ι C V D).obj (𝟙_ D)) ((ι C V D).obj d)).hom.app (𝟙_ C ⊗ x)
Module: Mathlib.CategoryTheory.Preadditive.HomOrthogonal

Goal state before:
pp: case w'
C : Type u
inst✝⁵ : Category.{v, u} C
ι : Type u_1
s : ι → C
inst✝⁴ : Preadditive C
inst✝³ : HasFiniteBiproducts C
o : HomOrthogonal s
α β γ : Type
inst✝² : Finite α
inst✝¹ : Fintype β
inst✝ : Finite γ
f : α → ι
g : β → ι
h : γ → ι
z : (⨁ fun a ↦ s (f a)) ⟶ ⨁ fun b ↦ s (g b)
w : (⨁ fun b ↦ s (g b)) ⟶ ⨁ fun c ↦ s (h c)
c : γ
a : α
j_property✝ : a ∈ f ⁻¹' {h c}
j_property : f a = h c
b : β
nm : b ∉ g ⁻¹' {h c}
⊢ eqToHom ⋯ ≫
      biproduct.ι (fun a ↦ s (f a)) a ≫
        z ≫
          ((biproduct.π (fun b ↦ s (g b)) b ≫ biproduct.ι (fun b ↦ s (g b)) b) ≫ w) ≫ biproduct.π (fun b ↦ s (h b)) c =
    0

Tactic:
simp only [Set.mem_preimage, Set.mem_singleton_iff] at nm

Goal state after:
case w'
C : Type u
inst✝⁵ : Category.{v, u} C
ι : Type u_1
s : ι → C
inst✝⁴ : Preadditive C
inst✝³ : HasFiniteBiproducts C
o : HomOrthogonal s
α β γ : Type
inst✝² : Finite α
inst✝¹ : Fintype β
inst✝ : Finite γ
f : α → ι
g : β → ι
h : γ → ι
z : (⨁ fun a ↦ s (f a)) ⟶ ⨁ fun b ↦ s (g b)
w : (⨁ fun b ↦ s (g b)) ⟶ ⨁ fun c ↦ s (h c)
c : γ
a : α
j_property✝ : a ∈ f ⁻¹' {h c}
j_property : f a = h c
b : β
nm : ¬g b = h c
⊢ eqToHom ⋯ ≫
      biproduct.ι (fun a ↦ s (f a)) a ≫
        z ≫
          ((biproduct.π (fun b ↦ s (g b)) b ≫ biproduct.ι (fun b ↦ s (g b)) b) ≫ w) ≫ biproduct.π (fun b ↦ s (h b)) c =
    0
Module: Mathlib.CategoryTheory.Preadditive.Schur

Goal state before:
pp: C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Preadditive C
𝕜 : Type u_2
inst✝² : Field 𝕜
inst✝¹ : IsAlgClosed 𝕜
inst✝ : Linear 𝕜 C
X : C
isIso_iff_nonzero : ∀ (f : X ⟶ X), IsIso f ↔ f ≠ 0
I : FiniteDimensional 𝕜 (X ⟶ X)
id_nonzero : 𝟙 X ≠ 0
f : X ⟶ X
this : Nontrivial (End X)
⊢ ∃ c, c • 𝟙 X = f

Tactic:
have : FiniteDimensional 𝕜 (End X) := I

Goal state after:
C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Preadditive C
𝕜 : Type u_2
inst✝² : Field 𝕜
inst✝¹ : IsAlgClosed 𝕜
inst✝ : Linear 𝕜 C
X : C
isIso_iff_nonzero : ∀ (f : X ⟶ X), IsIso f ↔ f ≠ 0
I : FiniteDimensional 𝕜 (X ⟶ X)
id_nonzero : 𝟙 X ≠ 0
f : X ⟶ X
this✝ : Nontrivial (End X)
this : FiniteDimensional 𝕜 (End X)
⊢ ∃ c, c • 𝟙 X = f
Module: Mathlib.CategoryTheory.Preadditive.Mat

Goal state before:
pp: case pos
C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
inst✝ : Preadditive C
n : ℕ
f : Fin n → Mat_ C
j j' : Fin n
x : (f j).ι
y : (f j').ι
h : j = j'
h' : ⋯ ▸ x = y
⊢ eqToHom ⋯ = eqToHom ⋯ x y

Tactic:
subst h h'
                simp only [CategoryTheory.eqToHom_refl, CategoryTheory.Mat_.id_apply_self]

Goal state after:
Module: Mathlib.CategoryTheory.Preadditive.Mat

Goal state before:
pp: case neg
C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
inst✝ : Preadditive C
n : ℕ
f : Fin n → Mat_ C
j : Fin n
x y : (f j).ι
h' : ¬⋯ ▸ x = y
⊢ 0 = eqToHom ⋯ x y

Tactic:
rw [eqToHom_refl, id_apply_of_ne _ _ _ h']

Goal state after:
Module: Mathlib.CategoryTheory.Presentable.Directed

Goal state before:
pp: J : Type w
inst✝¹ : SmallCategory J
κ : Cardinal.{w}
inst✝ : Fact κ.IsRegular
ι : Type u_1
D : ι → Diagram J κ
hι : HasCardinalLT ι κ
i✝ j✝ : J
f✝ : i✝ ⟶ j✝
hf : (⨆ i, (D i).W) f✝
⊢ (⨆ i, (D i).P) i✝

Tactic:
by
    simp only [MorphismProperty.iSup_iff, iSup_apply, iSup_Prop_eq] at hf ⊢
    obtain ⟨i, hi⟩ := hf
    exact ⟨i, (D i).src hi⟩

Goal state after:
Module: Mathlib.CategoryTheory.Presentable.CardinalDirectedPoset

Goal state before:
pp: κ : Cardinal.{u}
inst✝¹ : Fact κ.IsRegular
J : CardinalDirectedPoset κ
κ' : Cardinal.{u}
inst✝ : Fact κ'.IsRegular
h : κ ≤ κ'
x✝ : IsCardinalPresentable J κ'
X : Subtype (J.PropSetWithTop κ')
f : J ⟶ (functorOfPredicateSet (J.PropSetWithTop κ')).obj X
hf : f ≫ (J.coconeWithTop κ').ι.app X = ObjectProperty.homMk (PartOrdEmb.ofHom WithTop.coeOrderHom)
x : (fun X ↦ ↑X.obj) J
⊢ (⇑(OrderEmbedding.subtype fun x ↦ x ∈ ↑X) ∘ ⇑(ConcreteCategory.hom f)) x = WithTop.coeOrderHom x

Tactic:
exact ConcreteCategory.congr_hom hf x

Goal state after:
Module: Mathlib.CategoryTheory.Presentable.Directed

Goal state before:
pp: J : Type w
inst✝² : SmallCategory J
κ : Cardinal.{w}
inst✝¹ : Fact κ.IsRegular
inst✝ : IsCardinalFiltered J κ
hJ : ∀ (e : J), ∃ m x, IsEmpty (m ⟶ e)
ι : Type w
D : ι → DiagramWithUniqueTerminal J κ
hι : HasCardinalLT ι κ
m₀ : ι → J
t₀ : (i : ι) → (D i).top ⟶ m₀ i
hm₀ : ∀ (i : ι), IsEmpty (m₀ i ⟶ (D i).top)
m₁ : J := max m₀ hι
t₁ : (i : ι) → m₀ i ⟶ m₁ := fun i ↦ toMax m₀ hι i
u : (i : ι) → (D i).top ⟶ m₁ := fun i ↦ t₀ i ≫ t₁ i
S : Type (max 0 w) := { x // (D x.1).P x.2.2 ∧ (D x.2.1).P x.2.2 }
shape : MultispanShape :=
  { L := { x // (D x.1).P x.2.2 ∧ (D x.2.1).P x.2.2 }, R := PUnit.{w + 1}, fst := fun x ↦ PUnit.unit,
    snd := fun x ↦ PUnit.unit }
index : MultispanIndex shape J :=
  { left := fun x ↦ (↑x).2.2, right := fun x ↦ m₁, fst := fun x ↦ (D (↑x).1).isTerminal.lift ⋯ ≫ u (↑x).1,
    snd := fun x ↦ (D (↑x).2.1).isTerminal.lift ⋯ ≫ u (↑x).2.1 }
hκ : Cardinal.aleph0 ≤ κ
⊢ ∃ m u,
    (∀ (i : ι), IsEmpty (m ⟶ (D i).top)) ∧
      ∀ (i₁ i₂ : ι) (j : J) (hj₁ : (D i₁).P j) (hj₂ : (D i₂).P j),
        (D i₁).isTerminal.lift hj₁ ≫ u i₁ = (D i₂).isTerminal.lift hj₂ ≫ u i₂

Tactic:
have hL : HasCardinalLT shape.L κ := by
    have : HasCardinalLT (ι × (Σ (i : ι), Subtype (D i).P)) κ :=
      hasCardinalLT_prod hκ hι (hasCardinalLT_sigma _ _ hι (fun i ↦ (D i).hP))
    refine this.of_injective (fun ⟨⟨i₁, i₂, j⟩, h₁, h₂⟩ ↦ ⟨i₁, i₂, ⟨j, h₂⟩⟩) ?_
    rintro ⟨⟨i₁, i₂, j⟩, _, _⟩ ⟨⟨i₁', i₂', j'⟩, _, _⟩ h
    rw [Prod.ext_iff, Sigma.ext_iff] at h
    dsimp at h
    obtain rfl : i₁ = i₁' := h.1
    obtain rfl : i₂ = i₂' := h.2.1
    obtain rfl : j = j' := by simpa using h
    rfl

Goal state after:
J : Type w
inst✝² : SmallCategory J
κ : Cardinal.{w}
inst✝¹ : Fact κ.IsRegular
inst✝ : IsCardinalFiltered J κ
hJ : ∀ (e : J), ∃ m x, IsEmpty (m ⟶ e)
ι : Type w
D : ι → DiagramWithUniqueTerminal J κ
hι : HasCardinalLT ι κ
m₀ : ι → J
t₀ : (i : ι) → (D i).top ⟶ m₀ i
hm₀ : ∀ (i : ι), IsEmpty (m₀ i ⟶ (D i).top)
m₁ : J := max m₀ hι
t₁ : (i : ι) → m₀ i ⟶ m₁ := fun i ↦ toMax m₀ hι i
u : (i : ι) → (D i).top ⟶ m₁ := fun i ↦ t₀ i ≫ t₁ i
S : Type (max 0 w) := { x // (D x.1).P x.2.2 ∧ (D x.2.1).P x.2.2 }
shape : MultispanShape :=
  { L := { x // (D x.1).P x.2.2 ∧ (D x.2.1).P x.2.2 }, R := PUnit.{w + 1}, fst := fun x ↦ PUnit.unit,
    snd := fun x ↦ PUnit.unit }
index : MultispanIndex shape J :=
  { left := fun x ↦ (↑x).2.2, right := fun x ↦ m₁, fst := fun x ↦ (D (↑x).1).isTerminal.lift ⋯ ≫ u (↑x).1,
    snd := fun x ↦ (D (↑x).2.1).isTerminal.lift ⋯ ≫ u (↑x).2.1 }
hκ : Cardinal.aleph0 ≤ κ
hL : HasCardinalLT shape.L κ
⊢ ∃ m u,
    (∀ (i : ι), IsEmpty (m ⟶ (D i).top)) ∧
      ∀ (i₁ i₂ : ι) (j : J) (hj₁ : (D i₁).P j) (hj₂ : (D i₂).P j),
        (D i₁).isTerminal.lift hj₁ ≫ u i₁ = (D i₂).isTerminal.lift hj₂ ≫ u i₂
Module: Mathlib.CategoryTheory.Presentable.SharplyLT.Basic

Goal state before:
pp: case isSuccLimit
κ₁ κ₂ : Cardinal.{w}
inst✝¹ : Fact κ₁.IsRegular
inst✝ : Fact κ₂.IsRegular
h₀ : κ₁ < κ₂
X : Type w
Y : (B : Set X) → HasCardinalLT (↑B) κ₂ → Set (SetCardinalLT κ₁ ↑B)
hY : ∀ (B : Set X) (hB : HasCardinalLT (↑B) κ₂), HasCardinalLT (↑(Y B hB)) κ₂
m : (B : Set X) → (hB : HasCardinalLT (↑B) κ₂) → (C : SetCardinalLT κ₁ ↑B) → C ∈ Y B hB → X
A : Set X
hA : HasCardinalLT (↑A) κ₂
j : κ₁.ord.ToType
hj : Order.IsSuccLimit j
hj' : ∀ b < j, HasCardinalLT (↑(transfiniteIterate (φ Y m) b A)) κ₂
⊢ HasCardinalLT (↑(transfiniteIterate (φ Y m) j A)) κ₂

Tactic:
| isSuccLimit j hj hj' =>

Goal state after:
Module: Mathlib.CategoryTheory.Presentable.Type

Goal state before:
pp: X✝ X : Type u
κ : Cardinal.{u}
hκ : κ.IsRegular
hX : HasCardinalLT X κ
⊢ IsPresentable.{u, u, u + 1} X

Tactic:
have : Fact κ.IsRegular := ⟨hκ⟩

Goal state after:
X✝ X : Type u
κ : Cardinal.{u}
hκ : κ.IsRegular
hX : HasCardinalLT X κ
this : Fact κ.IsRegular
⊢ IsPresentable.{u, u, u + 1} X
Module: Mathlib.CategoryTheory.RepresentedBy

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
F : Cᵒᵖ ⥤ Type w
X : C
x : F.obj (op X)
⊢ F.IsRepresentedBy x ↔ IsIso (uliftYonedaEquiv.symm { down := x })

Tactic:
by
  rw [isRepresentedBy_iff, NatTrans.isIso_iff_isIso_app, Opposite.op_surjective.forall]
  refine forall_congr' fun Y ↦ ?_
  rw [isIso_iff_bijective, ← Function.Bijective.of_comp_iff _ Equiv.ulift.{w}.symm.bijective,
    ← Function.Bijective.of_comp_iff' Equiv.ulift.{v}.bijective]
  rfl

Goal state after:
Module: Mathlib.CategoryTheory.RegularCategory.Basic

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Regular C
X Y : C
f : X ⟶ Y
⊢ IsRegularEpi (strongEpiMonoFactorisation f).e

Tactic:
by
  dsimp [strongEpiMonoFactorisation]
  infer_instance

Goal state after:
Module: Mathlib.CategoryTheory.Sites.Coherent.ReflectsPreregular

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝⁷ : Category.{v_1, u_1} C
inst✝⁶ : Category.{v_2, u_2} D
F : C ⥤ D
inst✝⁵ : F.PreservesEffectiveEpis
inst✝⁴ : F.ReflectsEffectiveEpis
inst✝³ : F.EffectivelyEnough
inst✝² : Preregular D
inst✝¹ : F.Full
inst✝ : F.Faithful
X✝ Y✝ Z✝ : C
f : X✝ ⟶ Y✝
g : Z✝ ⟶ Y✝
x✝ : EffectiveEpi g
W : D
f' : W ⟶ F.obj X✝
w✝ : EffectiveEpi f'
i : W ⟶ F.obj Z✝
w : i ≫ F.map g = f' ≫ F.map f
⊢ ∃ W h, ∃ (_ : EffectiveEpi h), ∃ i, i ≫ g = h ≫ f

Tactic:
refine ⟨_, F.preimage (F.effectiveEpiOver W ≫ f'),
      ⟨F.effectiveEpi_of_map _ ?_, F.preimage (F.effectiveEpiOver W ≫ i), ?_⟩⟩

Goal state after:
case refine_1
C : Type u_1
D : Type u_2
inst✝⁷ : Category.{v_1, u_1} C
inst✝⁶ : Category.{v_2, u_2} D
F : C ⥤ D
inst✝⁵ : F.PreservesEffectiveEpis
inst✝⁴ : F.ReflectsEffectiveEpis
inst✝³ : F.EffectivelyEnough
inst✝² : Preregular D
inst✝¹ : F.Full
inst✝ : F.Faithful
X✝ Y✝ Z✝ : C
f : X✝ ⟶ Y✝
g : Z✝ ⟶ Y✝
x✝ : EffectiveEpi g
W : D
f' : W ⟶ F.obj X✝
w✝ : EffectiveEpi f'
i : W ⟶ F.obj Z✝
w : i ≫ F.map g = f' ≫ F.map f
⊢ EffectiveEpi (F.map (F.preimage (F.effectiveEpiOver W ≫ f')))

case refine_2
C : Type u_1
D : Type u_2
inst✝⁷ : Category.{v_1, u_1} C
inst✝⁶ : Category.{v_2, u_2} D
F : C ⥤ D
inst✝⁵ : F.PreservesEffectiveEpis
inst✝⁴ : F.ReflectsEffectiveEpis
inst✝³ : F.EffectivelyEnough
inst✝² : Preregular D
inst✝¹ : F.Full
inst✝ : F.Faithful
X✝ Y✝ Z✝ : C
f : X✝ ⟶ Y✝
g : Z✝ ⟶ Y✝
x✝ : EffectiveEpi g
W : D
f' : W ⟶ F.obj X✝
w✝ : EffectiveEpi f'
i : W ⟶ F.obj Z✝
w : i ≫ F.map g = f' ≫ F.map f
⊢ F.preimage (F.effectiveEpiOver W ≫ i) ≫ g = F.preimage (F.effectiveEpiOver W ≫ f') ≫ f
Module: Mathlib.CategoryTheory.Sites.Coherent.RegularSheaves

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
inst✝ : Preregular C
W : C
⊢ IsSheaf (regularTopology C) (yoneda.obj W)

Tactic:
regularTopology,

Goal state after:
C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
inst✝ : Preregular C
W : C
⊢ IsSheaf (regularCoverage C).toGrothendieck (yoneda.obj W)
Module: Mathlib.CategoryTheory.Sites.Finite

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : HasPullbacks C
X Y : C
u : Y ⟶ X
s : Presieve X
hs : s ∈ (Precoverage.finite C).coverings X
⊢ pullbackArrows u s ∈ (Precoverage.finite C).coverings Y

Tactic:
simpa using hs.image _

Goal state after:
Module: Mathlib.CategoryTheory.Sites.SheafHom

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
J : GrothendieckTopology C
A : Type u'
inst✝ : Category.{v', u'} A
F G : Cᵒᵖ ⥤ A
s : ↑(presheafHom F G).sections
⊢ (fun f ↦ ⟨fun x ↦ (Over.forget (unop x)).op.whiskerLeft f, ⋯⟩)
      ((fun s ↦ { app := fun X ↦ (↑s X).app (op (Over.mk (𝟙 (unop X)))), naturality := ⋯ }) s) =
    s

Tactic:
dsimp
    ext ⟨X⟩ ⟨Y : Over X⟩
    have H := s.2 Y.hom.op
    dsimp at H ⊢
    rw [← H]
    apply presheafHom_map_app_op_mk_id

Goal state after:
Module: Mathlib.CategoryTheory.Sites.SheafHom

Goal state before:
pp: case hex
C : Type u
inst✝¹ : Category.{v, u} C
A : Type u'
inst✝ : Category.{v', u'} A
F G : Cᵒᵖ ⥤ A
X : C
S : Sieve X
hG : ⦃Y : C⦄ → (f : Y ⟶ X) → IsLimit (G.mapCone (Sieve.pullback f S).arrows.cocone.op)
x : Presieve.FamilyOfElements (presheafHom F G) S.arrows
hx : x.Compatible
⊢ x.IsAmalgamation { app := fun Y ↦ app hG x hx (unop Y).hom, naturality := ⋯ }

Tactic:
rw [PresheafHom.isAmalgamation_iff _ _ hx]

Goal state after:
case hex
C : Type u
inst✝¹ : Category.{v, u} C
A : Type u'
inst✝ : Category.{v', u'} A
F G : Cᵒᵖ ⥤ A
X : C
S : Sieve X
hG : ⦃Y : C⦄ → (f : Y ⟶ X) → IsLimit (G.mapCone (Sieve.pullback f S).arrows.cocone.op)
x : Presieve.FamilyOfElements (presheafHom F G) S.arrows
hx : x.Compatible
⊢ ∀ (Y : C) (g : Y ⟶ X) (hg : S.arrows g),
    { app := fun Y ↦ app hG x hx (unop Y).hom, naturality := ⋯ }.app (op (Over.mk g)) =
      (x g hg).app (op (Over.mk (𝟙 Y)))
Module: Mathlib.CategoryTheory.Triangulated.Opposite.Functor

Goal state before:
pp: case e_a
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Category.{v_2, u_2} D
inst✝² : HasShift C ℤ
inst✝¹ : HasShift D ℤ
F : C ⥤ D
inst✝ : F.CommShift ℤ
X : Cᵒᵖ
n : ℤ
⊢ (shiftFunctorCompIsoId D (-n) n ⋯).hom.app (F.obj (unop X)) =
    (shiftFunctor D n).map
        ((shiftFunctorOpIso D n (-n) ⋯).inv.app (op (F.obj (unop X))) ≫
            (shiftFunctorOpIso D n (-n) ⋯).hom.app (op (F.obj (unop X)))).unop ≫
      (shiftFunctorCompIsoId D (-n) n ⋯).hom.app (F.obj (unop X))

Tactic:
Iso.inv_hom_id_app

Goal state after:
case e_a
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Category.{v_2, u_2} D
inst✝² : HasShift C ℤ
inst✝¹ : HasShift D ℤ
F : C ⥤ D
inst✝ : F.CommShift ℤ
X : Cᵒᵖ
n : ℤ
⊢ (shiftFunctorCompIsoId D (-n) n ⋯).hom.app (F.obj (unop X)) =
    (shiftFunctor D n).map (𝟙 ((shiftFunctor D (-n)).op.obj (op (F.obj (unop X))))).unop ≫
      (shiftFunctorCompIsoId D (-n) n ⋯).hom.app (F.obj (unop X))
Module: Mathlib.CategoryTheory.Triangulated.Adjunction

Goal state before:
pp: case refine_3
C : Type u_1
D : Type u_2
inst✝¹⁵ : Category.{v_1, u_1} C
inst✝¹⁴ : Category.{v_2, u_2} D
inst✝¹³ : HasZeroObject C
inst✝¹² : HasZeroObject D
inst✝¹¹ : Preadditive C
inst✝¹⁰ : Preadditive D
inst✝⁹ : HasShift C ℤ
inst✝⁸ : HasShift D ℤ
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁶ : ∀ (n : ℤ), (shiftFunctor D n).Additive
inst✝⁵ : Pretriangulated C
inst✝⁴ : Pretriangulated D
F : C ⥤ D
G : D ⥤ C
adj : F ⊣ G
inst✝³ : F.CommShift ℤ
inst✝² : G.CommShift ℤ
inst✝¹ : adj.CommShift ℤ
inst✝ : F.IsTriangulated
T : Triangle D
hT : T ∈ distinguishedTriangles
this✝¹ : G.Additive
Z : C
f : G.obj T.obj₂ ⟶ Z
g : Z ⟶ (shiftFunctor C 1).obj (G.obj T.obj₁)
mem : Triangle.mk (G.map T.mor₁) f g ∈ distinguishedTriangles
h : F.obj Z ⟶ T.obj₃
h₁ : F.map f ≫ h = adj.counit.app T.obj₂ ≫ T.mor₂
h₂ :
  F.map g ≫ (Functor.commShiftIso F 1).hom.app (G.obj T.obj₁) ≫ (shiftFunctor D 1).map (adj.counit.app T.obj₁) =
    h ≫ T.mor₃
h₁' : f ≫ adj.unit.app Z ≫ G.map h = G.map T.mor₂
h₂' : g ≫ (Functor.commShiftIso G 1).inv.app T.obj₁ = (adj.homEquiv Z T.obj₃) h ≫ G.map T.mor₃
this✝ : Mono ((adj.homEquiv Z T.obj₃) h)
this : IsIso ((adj.homEquiv Z T.obj₃) h)
⊢ g = adj.unit.app Z ≫ G.map (h ≫ T.mor₃) ≫ (Functor.commShiftIso G 1).hom.app T.obj₁

Tactic:
← h₂,

Goal state after:
case refine_3
C : Type u_1
D : Type u_2
inst✝¹⁵ : Category.{v_1, u_1} C
inst✝¹⁴ : Category.{v_2, u_2} D
inst✝¹³ : HasZeroObject C
inst✝¹² : HasZeroObject D
inst✝¹¹ : Preadditive C
inst✝¹⁰ : Preadditive D
inst✝⁹ : HasShift C ℤ
inst✝⁸ : HasShift D ℤ
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁶ : ∀ (n : ℤ), (shiftFunctor D n).Additive
inst✝⁵ : Pretriangulated C
inst✝⁴ : Pretriangulated D
F : C ⥤ D
G : D ⥤ C
adj : F ⊣ G
inst✝³ : F.CommShift ℤ
inst✝² : G.CommShift ℤ
inst✝¹ : adj.CommShift ℤ
inst✝ : F.IsTriangulated
T : Triangle D
hT : T ∈ distinguishedTriangles
this✝¹ : G.Additive
Z : C
f : G.obj T.obj₂ ⟶ Z
g : Z ⟶ (shiftFunctor C 1).obj (G.obj T.obj₁)
mem : Triangle.mk (G.map T.mor₁) f g ∈ distinguishedTriangles
h : F.obj Z ⟶ T.obj₃
h₁ : F.map f ≫ h = adj.counit.app T.obj₂ ≫ T.mor₂
h₂ :
  F.map g ≫ (Functor.commShiftIso F 1).hom.app (G.obj T.obj₁) ≫ (shiftFunctor D 1).map (adj.counit.app T.obj₁) =
    h ≫ T.mor₃
h₁' : f ≫ adj.unit.app Z ≫ G.map h = G.map T.mor₂
h₂' : g ≫ (Functor.commShiftIso G 1).inv.app T.obj₁ = (adj.homEquiv Z T.obj₃) h ≫ G.map T.mor₃
this✝ : Mono ((adj.homEquiv Z T.obj₃) h)
this : IsIso ((adj.homEquiv Z T.obj₃) h)
⊢ g =
    adj.unit.app Z ≫
      G.map
          (F.map g ≫
            (Functor.commShiftIso F 1).hom.app (G.obj T.obj₁) ≫ (shiftFunctor D 1).map (adj.counit.app T.obj₁)) ≫
        (Functor.commShiftIso G 1).hom.app T.obj₁
Module: Mathlib.CategoryTheory.Triangulated.TStructure.AbelianSubcategory

Goal state before:
pp: C : Type u_1
A : Type u_2
inst✝¹¹ : Category.{v_1, u_1} C
inst✝¹⁰ : HasZeroObject C
inst✝⁹ : Preadditive C
inst✝⁸ : HasShift C ℤ
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁶ : Pretriangulated C
inst✝⁵ : Category.{v_2, u_2} A
ι : A ⥤ C
hι : ∀ ⦃X Y : A⦄ ⦃n : ℤ⦄ (f : ι.obj X ⟶ (shiftFunctor C n).obj (ι.obj Y)), n < 0 → f = 0
inst✝⁴ : Preadditive A
inst✝³ : ι.Full
inst✝² : ι.Faithful
inst✝¹ : ι.Additive
hA : admissibleMorphism ι = ⊤
X₂ X₃ : A
π : X₂ ⟶ X₃
inst✝ : Epi π
X₁ : C
f₂ : ι.obj X₃ ⟶ X₁
f₃ : X₁ ⟶ (shiftFunctor C 1).obj (ι.obj X₂)
hT : Triangle.mk (ι.map π) f₂ f₃ ∈ distinguishedTriangles
this : admissibleMorphism ι π
⊢ ∃ X₁ i δ, Triangle.mk (ι.map i) (ι.map π) δ ∈ distinguishedTriangles

Tactic:
obtain ⟨K, Q, α, β, γ, hT'⟩ := this f₂ f₃ hT

Goal state after:
C : Type u_1
A : Type u_2
inst✝¹¹ : Category.{v_1, u_1} C
inst✝¹⁰ : HasZeroObject C
inst✝⁹ : Preadditive C
inst✝⁸ : HasShift C ℤ
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁶ : Pretriangulated C
inst✝⁵ : Category.{v_2, u_2} A
ι : A ⥤ C
hι : ∀ ⦃X Y : A⦄ ⦃n : ℤ⦄ (f : ι.obj X ⟶ (shiftFunctor C n).obj (ι.obj Y)), n < 0 → f = 0
inst✝⁴ : Preadditive A
inst✝³ : ι.Full
inst✝² : ι.Faithful
inst✝¹ : ι.Additive
hA : admissibleMorphism ι = ⊤
X₂ X₃ : A
π : X₂ ⟶ X₃
inst✝ : Epi π
X₁ : C
f₂ : ι.obj X₃ ⟶ X₁
f₃ : X₁ ⟶ (shiftFunctor C 1).obj (ι.obj X₂)
hT : Triangle.mk (ι.map π) f₂ f₃ ∈ distinguishedTriangles
this : admissibleMorphism ι π
K Q : A
α : (shiftFunctor C 1).obj (ι.obj K) ⟶ X₁
β : X₁ ⟶ ι.obj Q
γ : ι.obj Q ⟶ (shiftFunctor C 1).obj ((shiftFunctor C 1).obj (ι.obj K))
hT' : Triangle.mk α β γ ∈ distinguishedTriangles
⊢ ∃ X₁ i δ, Triangle.mk (ι.map i) (ι.map π) δ ∈ distinguishedTriangles
Module: Mathlib.CategoryTheory.Triangulated.TStructure.AbelianSubcategory

Goal state before:
pp: C : Type u_1
A : Type u_2
inst✝¹² : Category.{v_1, u_1} C
inst✝¹¹ : HasZeroObject C
inst✝¹⁰ : Preadditive C
inst✝⁹ : HasShift C ℤ
inst✝⁸ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁷ : Pretriangulated C
inst✝⁶ : Category.{v_2, u_2} A
ι : A ⥤ C
hι : ∀ ⦃X Y : A⦄ ⦃n : ℤ⦄ (f : ι.obj X ⟶ (shiftFunctor C n).obj (ι.obj Y)), n < 0 → f = 0
inst✝⁵ : Preadditive A
inst✝⁴ : ι.Full
inst✝³ : ι.Faithful
inst✝² : HasFiniteProducts A
inst✝¹ : ι.Additive
hA : admissibleMorphism ι = ⊤
inst✝ : IsTriangulated C
X₁ X₂ : A
f₁ : X₁ ⟶ X₂
X₃ : C
f₂ : ι.obj X₂ ⟶ X₃
f₃ : X₃ ⟶ (shiftFunctor C 1).obj (ι.obj X₁)
hT : Triangle.mk (ι.map f₁) f₂ f₃ ∈ distinguishedTriangles
this : admissibleMorphism ι f₁
⊢ Nonempty (Abelian.AbelianStruct f₁)

Tactic:
obtain ⟨K, Q, α, β, γ, hT'⟩ := this f₂ f₃ hT

Goal state after:
C : Type u_1
A : Type u_2
inst✝¹² : Category.{v_1, u_1} C
inst✝¹¹ : HasZeroObject C
inst✝¹⁰ : Preadditive C
inst✝⁹ : HasShift C ℤ
inst✝⁸ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁷ : Pretriangulated C
inst✝⁶ : Category.{v_2, u_2} A
ι : A ⥤ C
hι : ∀ ⦃X Y : A⦄ ⦃n : ℤ⦄ (f : ι.obj X ⟶ (shiftFunctor C n).obj (ι.obj Y)), n < 0 → f = 0
inst✝⁵ : Preadditive A
inst✝⁴ : ι.Full
inst✝³ : ι.Faithful
inst✝² : HasFiniteProducts A
inst✝¹ : ι.Additive
hA : admissibleMorphism ι = ⊤
inst✝ : IsTriangulated C
X₁ X₂ : A
f₁ : X₁ ⟶ X₂
X₃ : C
f₂ : ι.obj X₂ ⟶ X₃
f₃ : X₃ ⟶ (shiftFunctor C 1).obj (ι.obj X₁)
hT : Triangle.mk (ι.map f₁) f₂ f₃ ∈ distinguishedTriangles
this : admissibleMorphism ι f₁
K Q : A
α : (shiftFunctor C 1).obj (ι.obj K) ⟶ X₃
β : X₃ ⟶ ι.obj Q
γ : ι.obj Q ⟶ (shiftFunctor C 1).obj ((shiftFunctor C 1).obj (ι.obj K))
hT' : Triangle.mk α β γ ∈ distinguishedTriangles
⊢ Nonempty (Abelian.AbelianStruct f₁)
Module: Mathlib.Combinatorics.Additive.AP.Three.Defs

Goal state before:
pp: α : Type u_2
inst✝¹ : CommMonoid α
inst✝ : IsCancelMul α
s : Set α
a : α
⊢ ThreeGPFree (insert a s) ↔
    ThreeGPFree s ∧
      (∀ ⦃b : α⦄, b ∈ s → ∀ ⦃c : α⦄, c ∈ s → a * c = b * b → a = b) ∧
        ∀ ⦃b : α⦄, b ∈ s → ∀ ⦃c : α⦄, c ∈ s → b * c = a * a → b = a

Tactic:
refine ⟨fun hs ↦ ⟨hs.mono (subset_insert _ _),
    fun b hb c hc ↦ hs (Or.inl rfl) (Or.inr hb) (Or.inr hc),
    fun b hb c hc ↦ hs (Or.inr hb) (Or.inl rfl) (Or.inr hc)⟩, ?_⟩

Goal state after:
α : Type u_2
inst✝¹ : CommMonoid α
inst✝ : IsCancelMul α
s : Set α
a : α
⊢ (ThreeGPFree s ∧
      (∀ ⦃b : α⦄, b ∈ s → ∀ ⦃c : α⦄, c ∈ s → a * c = b * b → a = b) ∧
        ∀ ⦃b : α⦄, b ∈ s → ∀ ⦃c : α⦄, c ∈ s → b * c = a * a → b = a) →
    ThreeGPFree (insert a s)