mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.CategoryTheory.Sites.ConcreteSheafification

Goal state before:
pp: case h
C : Type u
inst✝⁶ : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝⁵ : Category.{w', w} D
FD : D → D → Type u_1
CD : D → Type t
inst✝⁴ : (X Y : D) → FunLike (FD X Y) (CD X) (CD Y)
instCC : ConcreteCategory D FD
inst✝³ : ∀ {X : C} (S : J.Cover X), PreservesLimitsOfShape (WalkingMulticospan S.shape) (forget D)
inst✝² : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
inst✝¹ : ∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)
inst✝ : ∀ (X : C), PreservesColimitsOfShape (J.Cover X)ᵒᵖ (forget D)
X : C
P : Cᵒᵖ ⥤ D
S✝ T : J.Cover X
x : Meq P S✝
y : Meq P T
S : J.Cover X
h1 : S ⟶ S✝
h2 : S ⟶ T
e : x.refine h1 = y.refine h2
⊢ (ConcreteCategory.hom ((J.diagram P X).map h1.op)) ((Meq.equiv P S✝).symm x) =
    (ConcreteCategory.hom ((J.diagram P X).map h2.op)) ((Meq.equiv P T).symm y)

Tactic:
apply Concrete.multiequalizer_ext

Goal state after:
case h
C : Type u
inst✝⁶ : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝⁵ : Category.{w', w} D
FD : D → D → Type u_1
CD : D → Type t
inst✝⁴ : (X Y : D) → FunLike (FD X Y) (CD X) (CD Y)
instCC : ConcreteCategory D FD
inst✝³ : ∀ {X : C} (S : J.Cover X), PreservesLimitsOfShape (WalkingMulticospan S.shape) (forget D)
inst✝² : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
inst✝¹ : ∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)
inst✝ : ∀ (X : C), PreservesColimitsOfShape (J.Cover X)ᵒᵖ (forget D)
X : C
P : Cᵒᵖ ⥤ D
S✝ T : J.Cover X
x : Meq P S✝
y : Meq P T
S : J.Cover X
h1 : S ⟶ S✝
h2 : S ⟶ T
e : x.refine h1 = y.refine h2
⊢ ∀ (t : (unop (op S)).shape.L),
    (ConcreteCategory.hom (Multiequalizer.ι ((unop (op S)).index P) t))
        ((ConcreteCategory.hom ((J.diagram P X).map h1.op)) ((Meq.equiv P S✝).symm x)) =
      (ConcreteCategory.hom (Multiequalizer.ι ((unop (op S)).index P) t))
        ((ConcreteCategory.hom ((J.diagram P X).map h2.op)) ((Meq.equiv P T).symm y))
Module: Mathlib.CategoryTheory.Sites.IsSheafFor

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
P : Cᵒᵖ ⥤ Type u_1
U : Sieve X
B : ⦃Y : C⦄ → ⦃f : Y ⟶ X⦄ → U.arrows f → Sieve Y
hU : IsSheafFor P U.arrows
hB : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄ (hf : U.arrows f), IsSheafFor P (B hf).arrows
hB' : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄ (h : U.arrows f) ⦃Z : C⦄ (g : Z ⟶ Y), IsSeparatedFor P (Sieve.pullback g (B h)).arrows
s : FamilyOfElements P (Sieve.bind U.arrows B).arrows
hs : s.Compatible
y : ⦃Y : C⦄ → ⦃f : Y ⟶ X⦄ → (hf : U.arrows f) → FamilyOfElements P (B hf).arrows := fun Y f hf Z g hg ↦ s (g ≫ f) ⋯
Y : C
f : Y ⟶ X
H : U.arrows f
Y₁ Y₂ : C
⊢ ∀ ⦃Z : C⦄ (g₁ : Z ⟶ Y₁) (g₂ : Z ⟶ Y₂) ⦃f₁ : Y₁ ⟶ Y⦄ ⦃f₂ : Y₂ ⟶ Y⦄ (h₁ : (B H).arrows f₁) (h₂ : (B H).arrows f₂),
    g₁ ≫ f₁ = g₂ ≫ f₂ →
      (ConcreteCategory.hom (P.map g₁.op)) (y H f₁ h₁) = (ConcreteCategory.hom (P.map g₂.op)) (y H f₂ h₂)

Tactic:
Z

Goal state after:
C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
P : Cᵒᵖ ⥤ Type u_1
U : Sieve X
B : ⦃Y : C⦄ → ⦃f : Y ⟶ X⦄ → U.arrows f → Sieve Y
hU : IsSheafFor P U.arrows
hB : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄ (hf : U.arrows f), IsSheafFor P (B hf).arrows
hB' : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄ (h : U.arrows f) ⦃Z : C⦄ (g : Z ⟶ Y), IsSeparatedFor P (Sieve.pullback g (B h)).arrows
s : FamilyOfElements P (Sieve.bind U.arrows B).arrows
hs : s.Compatible
y : ⦃Y : C⦄ → ⦃f : Y ⟶ X⦄ → (hf : U.arrows f) → FamilyOfElements P (B hf).arrows := fun Y f hf Z g hg ↦ s (g ≫ f) ⋯
Y : C
f : Y ⟶ X
H : U.arrows f
Y₁ Y₂ Z : C
⊢ ∀ (g₁ : Z ⟶ Y₁) (g₂ : Z ⟶ Y₂) ⦃f₁ : Y₁ ⟶ Y⦄ ⦃f₂ : Y₂ ⟶ Y⦄ (h₁ : (B H).arrows f₁) (h₂ : (B H).arrows f₂),
    g₁ ≫ f₁ = g₂ ≫ f₂ →
      (ConcreteCategory.hom (P.map g₁.op)) (y H f₁ h₁) = (ConcreteCategory.hom (P.map g₂.op)) (y H f₂ h₂)
Module: Mathlib.CategoryTheory.Sites.CompatiblePlus

Goal state before:
pp: C : Type u
inst✝⁸ : Category.{v, u} C
J : GrothendieckTopology C
D : Type u_1
inst✝⁷ : Category.{v_1, u_1} D
E : Type u_2
inst✝⁶ : Category.{v_2, u_2} E
F : D ⥤ E
inst✝⁵ : ∀ (J : MulticospanShape), HasLimitsOfShape (WalkingMulticospan J) D
inst✝⁴ : ∀ (J : MulticospanShape), HasLimitsOfShape (WalkingMulticospan J) E
inst✝³ : ∀ (X : C) (W : J.Cover X) (P : Cᵒᵖ ⥤ D), PreservesLimit (W.index P).multicospan F
P : Cᵒᵖ ⥤ D
inst✝² : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
inst✝¹ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ E
inst✝ : ∀ (X : C), PreservesColimitsOfShape (J.Cover X)ᵒᵖ F
X : Cᵒᵖ
⊢ (J.plusObj P ⋙ F).obj X ≅ (J.plusObj (P ⋙ F)).obj X

Tactic:
refine ?_ ≪≫ HasColimit.isoOfNatIso (J.diagramCompIso F P X.unop)
      refine
        (isColimitOfPreserves F
              (colimit.isColimit (J.diagram P (unop X)))).coconePointUniqueUpToIso
          (colimit.isColimit _)

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

Goal state before:
pp: case hS
C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
P : Cᵒᵖ ⥤ Type u_1
R S : Sieve X
hR : IsSheafFor P R.arrows
hR' : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, S.arrows f → IsSeparatedFor P (Sieve.pullback f R).arrows
hS : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, R.arrows f → IsSheafFor P (Sieve.pullback f S).arrows
this : (Sieve.bind R.arrows fun Y f x ↦ Sieve.pullback f S).arrows ≤ S.arrows
Y : C
f : Y ⟶ X
hf : R.arrows f
⊢ ∀ ⦃Z : C⦄ (g : Z ⟶ Y), IsSeparatedFor P (Sieve.pullback g (Sieve.pullback f S)).arrows

Tactic:
Z

Goal state after:
case hS
C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
P : Cᵒᵖ ⥤ Type u_1
R S : Sieve X
hR : IsSheafFor P R.arrows
hR' : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, S.arrows f → IsSeparatedFor P (Sieve.pullback f R).arrows
hS : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, R.arrows f → IsSheafFor P (Sieve.pullback f S).arrows
this : (Sieve.bind R.arrows fun Y f x ↦ Sieve.pullback f S).arrows ≤ S.arrows
Y : C
f : Y ⟶ X
hf : R.arrows f
Z : C
⊢ ∀ (g : Z ⟶ Y), IsSeparatedFor P (Sieve.pullback g (Sieve.pullback f S)).arrows
Module: Mathlib.CategoryTheory.Sites.IsSheafFor

Goal state before:
pp: case mp
C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
P : Cᵒᵖ ⥤ Type u_1
R S : Sieve X
hR : IsSheafFor P R.arrows
hR' : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, S.arrows f → IsSeparatedFor P (Sieve.pullback f R).arrows
hS : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, R.arrows f → IsSheafFor P (Sieve.pullback f S).arrows
this : (Sieve.bind R.arrows fun Y f x ↦ Sieve.pullback f S).arrows ≤ S.arrows
Y : C
f : Y ⟶ X
hf : S.arrows f
Z : C
g : Z ⟶ Y
W : C
k : Z ⟶ W
l : W ⟶ X
hl : R.arrows l
left✝ : ((fun T k x ↦ Sieve.pullback k S) W l hl).arrows k
comm : k ≫ l = g ≫ f
⊢ (Sieve.pullback f R).arrows g

Tactic:
rw [pullback_apply, ← comm]

Goal state after:
case mp
C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
P : Cᵒᵖ ⥤ Type u_1
R S : Sieve X
hR : IsSheafFor P R.arrows
hR' : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, S.arrows f → IsSeparatedFor P (Sieve.pullback f R).arrows
hS : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄, R.arrows f → IsSheafFor P (Sieve.pullback f S).arrows
this : (Sieve.bind R.arrows fun Y f x ↦ Sieve.pullback f S).arrows ≤ S.arrows
Y : C
f : Y ⟶ X
hf : S.arrows f
Z : C
g : Z ⟶ Y
W : C
k : Z ⟶ W
l : W ⟶ X
hl : R.arrows l
left✝ : ((fun T k x ↦ Sieve.pullback k S) W l hl).arrows k
comm : k ≫ l = g ≫ f
⊢ R.arrows (k ≫ l)
Module: Mathlib.CategoryTheory.Sites.Sheafification

Goal state before:
pp: C : Type u₁
inst✝² : Category.{v₁, u₁} C
J : GrothendieckTopology C
D : Type u_1
inst✝¹ : Category.{v_1, u_1} D
inst✝ : HasWeakSheafify J D
P Q : Cᵒᵖ ⥤ D
η : P ⟶ Q
hQ : Presheaf.IsSheaf J Q
γ : sheafify J P ⟶ Q
h : (sheafificationAdjunction J D).unit.app P ≫ γ = η
γ' : (presheafToSheaf J D).obj P ⟶ { obj := Q, property := hQ } := { hom := γ }
⊢ (sheafificationAdjunction J D).unit.app P ≫ (sheafToPresheaf J D).map γ' = η

Tactic:
exact h

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

Goal state before:
pp: C : Type u
inst✝² : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝¹ : Category.{w', w} D
K : Type z
inst✝ : Category.{z', z} K
F : K ⥤ Sheaf J D
E : Cone (F ⋙ sheafToPresheaf J D)
X : C
W : J.Cover X
S : Multifork (W.index E.pt)
i j : K
f : i ⟶ j
ii : W.Arrow
⊢ S.ι ii ≫ (E.π.app j).app (op ii.Y) = (S.ι ii ≫ (E.π.app i).app (op ii.Y)) ≫ (F.map f).hom.app (op ii.Y)

Tactic:
erw [Category.assoc, ← E.w f]

Goal state after:
C : Type u
inst✝² : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝¹ : Category.{w', w} D
K : Type z
inst✝ : Category.{z', z} K
F : K ⥤ Sheaf J D
E : Cone (F ⋙ sheafToPresheaf J D)
X : C
W : J.Cover X
S : Multifork (W.index E.pt)
i j : K
f : i ⟶ j
ii : W.Arrow
⊢ S.ι ii ≫ (E.π.app i ≫ (F ⋙ sheafToPresheaf J D).map f).app (op ii.Y) =
    S.ι ii ≫ (E.π.app i).app (op ii.Y) ≫ (F.map f).hom.app (op ii.Y)
Module: Mathlib.CategoryTheory.Sites.CompatiblePlus

Goal state before:
pp: C : Type u
inst✝⁸ : Category.{v, u} C
J : GrothendieckTopology C
D : Type u_1
inst✝⁷ : Category.{v_1, u_1} D
E : Type u_2
inst✝⁶ : Category.{v_2, u_2} E
F : D ⥤ E
inst✝⁵ : ∀ (J : MulticospanShape), HasLimitsOfShape (WalkingMulticospan J) D
inst✝⁴ : ∀ (J : MulticospanShape), HasLimitsOfShape (WalkingMulticospan J) E
inst✝³ : ∀ (X : C) (W : J.Cover X) (P : Cᵒᵖ ⥤ D), PreservesLimit (W.index P).multicospan F
P : Cᵒᵖ ⥤ D
inst✝² : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
inst✝¹ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ E
inst✝ : ∀ (X : C), PreservesColimitsOfShape (J.Cover X)ᵒᵖ F
⊢ whiskerRight (J.toPlus P) F ≫ (J.plusCompIso F P).hom = J.toPlus (P ⋙ F)

Tactic:
by
  ext
  dsimp [toPlus]
  simp only [ι_plusCompIso_hom, Functor.map_comp, Category.assoc]
  simp only [← Category.assoc]
  congr 1
  dsimp only [diagram] -- Need to unfold `diagram` before `ext` applies.
  ext a
  rw [Category.assoc, diagramCompIso_hom_ι, ← F.map_comp]
  simp only [unop_op, limit.lift_π, Multifork.ofι_π_app, Functor.comp_obj, Functor.comp_map]

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

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝² : Category.{w', w} D
inst✝¹ : ∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)
inst✝ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
P Q : Cᵒᵖ ⥤ D
η : P ⟶ Q
hQ : Presheaf.IsSheaf J Q
γ : J.sheafify P ⟶ Q
h : J.toSheafify P ≫ γ = η
⊢ (J.toPlus P ≫ J.plusMap (J.toPlus P)) ≫ γ = η

Tactic:
exact h

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

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝² : Category.{w', w} D
inst✝¹ : ∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)
inst✝ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
P Q : Cᵒᵖ ⥤ D
η γ : J.sheafify P ⟶ Q
hQ : Presheaf.IsSheaf J Q
h : J.toSheafify P ≫ η = J.toSheafify P ≫ γ
⊢ (J.toPlus P ≫ J.plusMap (J.toPlus P)) ≫ η = (J.toPlus P ≫ J.plusMap (J.toPlus P)) ≫ γ

Tactic:
exact h

Goal state after:
Module: Mathlib.Topology.Category.TopCat.Limits.Products

Goal state before:
pp: case refine_1
J : Type v
inst✝ : Category.{w, v} J
X Y : TopCat
S : Cone (pair X Y)
m : S.pt ⟶ (X.prodBinaryFan Y).pt
x : ↑S.pt
h :
  (ConcreteCategory.hom (m ≫ (X.prodBinaryFan Y).π.app { as := WalkingPair.left })) x =
    (ConcreteCategory.hom (S.π.app { as := WalkingPair.left })) x
⊢ ((ConcreteCategory.hom m) x).1 =
    ((ConcreteCategory.hom
          (ofHom
            { toFun := fun s ↦ ((ConcreteCategory.hom (BinaryFan.fst S)) s, (ConcreteCategory.hom (BinaryFan.snd S)) s),
              continuous_toFun := ⋯ }))
        x).1

Tactic:
exact h

Goal state after:
Module: Mathlib.Topology.Category.TopCat.Limits.Products

Goal state before:
pp: case refine_2
J : Type v
inst✝ : Category.{w, v} J
X Y : TopCat
S : Cone (pair X Y)
m : S.pt ⟶ (X.prodBinaryFan Y).pt
x : ↑S.pt
h :
  (ConcreteCategory.hom (m ≫ (X.prodBinaryFan Y).π.app { as := WalkingPair.right })) x =
    (ConcreteCategory.hom (S.π.app { as := WalkingPair.right })) x
⊢ ((ConcreteCategory.hom m) x).2 =
    ((ConcreteCategory.hom
          (ofHom
            { toFun := fun s ↦ ((ConcreteCategory.hom (BinaryFan.fst S)) s, (ConcreteCategory.hom (BinaryFan.snd S)) s),
              continuous_toFun := ⋯ }))
        x).2

Tactic:
exact h

Goal state after:
Module: Mathlib.Topology.Category.TopCat.Limits.Products

Goal state before:
pp: case mp
W X Y Z : TopCat
f : W ⟶ Y
g : X ⟶ Z
y : ↑(W ⨯ X)
⊢ (∃ y_1, (ConcreteCategory.hom f) y_1 = (ConcreteCategory.hom (prod.map f g ≫ prod.fst)) y) ∧
    ∃ y_1, (ConcreteCategory.hom g) y_1 = (ConcreteCategory.hom (prod.map f g ≫ prod.snd)) y

Tactic:
Limits.prod.map_fst,

Goal state after:
case mp
W X Y Z : TopCat
f : W ⟶ Y
g : X ⟶ Z
y : ↑(W ⨯ X)
⊢ (∃ y_1, (ConcreteCategory.hom f) y_1 = (ConcreteCategory.hom (prod.fst ≫ f)) y) ∧
    ∃ y_1, (ConcreteCategory.hom g) y_1 = (ConcreteCategory.hom (prod.map f g ≫ prod.snd)) y
Module: Mathlib.Topology.Category.TopCat.Limits.Pullbacks

Goal state before:
pp: case mp
X Y Z : TopCat
f : X ⟶ Z
g : Y ⟶ Z
U : Set ↑X
x : ↑Y
⊢ x ∈ ⇑(ConcreteCategory.hom (pullback.snd f g)) '' ⇑(ConcreteCategory.hom (pullback.fst f g)) ⁻¹' U →
    x ∈ ⇑(ConcreteCategory.hom g) ⁻¹' ⇑(ConcreteCategory.hom f) '' U

pp: case mpr
X Y Z : TopCat
f : X ⟶ Z
g : Y ⟶ Z
U : Set ↑X
x : ↑Y
⊢ x ∈ ⇑(ConcreteCategory.hom g) ⁻¹' ⇑(ConcreteCategory.hom f) '' U →
    x ∈ ⇑(ConcreteCategory.hom (pullback.snd f g)) '' ⇑(ConcreteCategory.hom (pullback.fst f g)) ⁻¹' U

Tactic:
· rintro ⟨y, hy, rfl⟩
    exact
      ⟨(pullback.fst f g) y, hy, CategoryTheory.congr_fun pullback.condition y⟩

Goal state after:
case mpr
X Y Z : TopCat
f : X ⟶ Z
g : Y ⟶ Z
U : Set ↑X
x : ↑Y
⊢ x ∈ ⇑(ConcreteCategory.hom g) ⁻¹' ⇑(ConcreteCategory.hom f) '' U →
    x ∈ ⇑(ConcreteCategory.hom (pullback.snd f g)) '' ⇑(ConcreteCategory.hom (pullback.fst f g)) ⁻¹' U
Module: Mathlib.Topology.Category.TopCat.Limits.Pullbacks

Goal state before:
pp: case mpr.one
X Y : TopCat
f g : X ⟶ Y
c : Cofork f g
hc : IsColimit c
U : Set ↑c.pt
h : IsOpen (⇑(ConcreteCategory.hom c.π) ⁻¹' U)
⊢ IsOpen (⇑(ConcreteCategory.hom (c.ι.app WalkingParallelPair.one)) ⁻¹' U)

Tactic:
exact h

Goal state after:
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: case h₁.left
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u''
inst✝ : Category.{v'', u''} D
X Y : C
X'✝ Y'✝ : Type u
αX✝ : X'✝ ⟶ PUnit.{u + 1}
αY✝ : Y'✝ ⟶ PUnit.{u + 1}
f : (Types.binaryCoproductCocone X'✝ Y'✝).pt ⟶ (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}).pt
hαX :
  αX✝ ≫ BinaryCofan.inl (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
hαY :
  αY✝ ≫ BinaryCofan.inr (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
s : PullbackCone f (BinaryCofan.inl (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}))
this :
  ∀ (x : (fun X ↦ X) s.pt),
    ∃ x_1,
      (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) x_1 ∧
        ∀ (y : X'✝), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) y → y = x_1
⊢ { l //
    l ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).fst = s.fst ∧
      l ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).snd = s.snd ∧
        ∀ {m : s.pt ⟶ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).pt},
          m ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).fst = s.fst →
            m ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).snd = s.snd → m = l }

Tactic:
choose l hl hl' using this

Goal state after:
case h₁.left
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u''
inst✝ : Category.{v'', u''} D
X Y : C
X'✝ Y'✝ : Type u
αX✝ : X'✝ ⟶ PUnit.{u + 1}
αY✝ : Y'✝ ⟶ PUnit.{u + 1}
f : (Types.binaryCoproductCocone X'✝ Y'✝).pt ⟶ (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}).pt
hαX :
  αX✝ ≫ BinaryCofan.inl (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
hαY :
  αY✝ ≫ BinaryCofan.inr (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
s : PullbackCone f (BinaryCofan.inl (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}))
l : s.pt → X'✝
hl : ∀ (x : s.pt), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) (l x)
hl' : ∀ (x : s.pt) (y : X'✝), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) y → y = l x
⊢ { l //
    l ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).fst = s.fst ∧
      l ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).snd = s.snd ∧
        ∀ {m : s.pt ⟶ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).pt},
          m ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).fst = s.fst →
            m ≫ (PullbackCone.mk (BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝)) αX✝ ⋯).snd = s.snd → m = l }
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: case h₁.right
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u''
inst✝ : Category.{v'', u''} D
X Y : C
X'✝ Y'✝ : Type u
αX✝ : X'✝ ⟶ PUnit.{u + 1}
αY✝ : Y'✝ ⟶ PUnit.{u + 1}
f : (Types.binaryCoproductCocone X'✝ Y'✝).pt ⟶ (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}).pt
hαX :
  αX✝ ≫ BinaryCofan.inl (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
hαY :
  αY✝ ≫ BinaryCofan.inr (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
s : PullbackCone f (BinaryCofan.inr (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}))
this :
  ∀ (x : (fun X ↦ X) s.pt),
    ∃ x_1,
      (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inr y) x_1 ∧
        ∀ (y : Y'✝), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inr y) y → y = x_1
⊢ { l //
    l ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).fst = s.fst ∧
      l ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).snd = s.snd ∧
        ∀ {m : s.pt ⟶ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).pt},
          m ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).fst = s.fst →
            m ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).snd = s.snd → m = l }

Tactic:
choose l hl hl' using this

Goal state after:
case h₁.right
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u''
inst✝ : Category.{v'', u''} D
X Y : C
X'✝ Y'✝ : Type u
αX✝ : X'✝ ⟶ PUnit.{u + 1}
αY✝ : Y'✝ ⟶ PUnit.{u + 1}
f : (Types.binaryCoproductCocone X'✝ Y'✝).pt ⟶ (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}).pt
hαX :
  αX✝ ≫ BinaryCofan.inl (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inl (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
hαY :
  αY✝ ≫ BinaryCofan.inr (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}) =
    BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝) ≫ f
s : PullbackCone f (BinaryCofan.inr (Types.binaryCoproductCocone PUnit.{u + 1} PUnit.{u + 1}))
l : s.pt → Y'✝
hl : ∀ (x : s.pt), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inr y) (l x)
hl' : ∀ (x : s.pt) (y : Y'✝), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inr y) y → y = l x
⊢ { l //
    l ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).fst = s.fst ∧
      l ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).snd = s.snd ∧
        ∀ {m : s.pt ⟶ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).pt},
          m ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).fst = s.fst →
            m ≫ (PullbackCone.mk (BinaryCofan.inr (Types.binaryCoproductCocone X'✝ Y'✝)) αY✝ ⋯).snd = s.snd → m = l }
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: case h₁.left
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u''
inst✝ : Category.{v'', u''} D
X Y : C
X' Y' : TopCat
αX : X' ⟶ TopCat.of PUnit.{u + 1}
αY : Y' ⟶ TopCat.of PUnit.{u + 1}
f : (X'.binaryCofan Y').pt ⟶ ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).pt
hαX : αX ≫ ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inl = (X'.binaryCofan Y').inl ≫ f
hαY : αY ≫ ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inr = (X'.binaryCofan Y').inr ≫ f
s : PullbackCone f ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inl
this :
  ∀ (x : ↑s.pt),
    ∃ x_1,
      (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) x_1 ∧
        ∀ (y : ↑X'), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) y → y = x_1
⊢ { l //
    l ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).fst = s.fst ∧
      l ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).snd = s.snd ∧
        ∀ {m : s.pt ⟶ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).pt},
          m ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).fst = s.fst →
            m ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).snd = s.snd → m = l }

Tactic:
choose l hl hl' using this

Goal state after:
case h₁.left
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
D : Type u''
inst✝ : Category.{v'', u''} D
X Y : C
X' Y' : TopCat
αX : X' ⟶ TopCat.of PUnit.{u + 1}
αY : Y' ⟶ TopCat.of PUnit.{u + 1}
f : (X'.binaryCofan Y').pt ⟶ ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).pt
hαX : αX ≫ ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inl = (X'.binaryCofan Y').inl ≫ f
hαY : αY ≫ ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inr = (X'.binaryCofan Y').inr ≫ f
s : PullbackCone f ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inl
l : ↑s.pt → ↑X'
hl : ∀ (x : ↑s.pt), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) (l x)
hl' : ∀ (x : ↑s.pt) (y : ↑X'), (fun y ↦ (ConcreteCategory.hom s.fst) x = Sum.inl y) y → y = l x
⊢ { l //
    l ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).fst = s.fst ∧
      l ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).snd = s.snd ∧
        ∀ {m : s.pt ⟶ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).pt},
          m ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).fst = s.fst →
            m ≫ (PullbackCone.mk (X'.binaryCofan Y').inl αX ⋯).snd = s.snd → m = l }