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

Goal state before:
pp: case mpr
C : Type u₁
inst✝ : Category.{v₁, u₁} C
P : Cᵒᵖ ⥤ Type w
X : C
S : Sieve X
x : FamilyOfElements P S.arrows
h : x.SieveCompatible
Y₁ Y₂ Z : C
g₁ : Z ⟶ Y₁
g₂ : Z ⟶ Y₂
f₁ : Y₁ ⟶ X
f₂ : Y₂ ⟶ X
h₁ : S.arrows f₁
h₂ : S.arrows f₂
⊢ g₁ ≫ f₁ = g₂ ≫ f₂ → (ConcreteCategory.hom (P.map g₁.op)) (x f₁ h₁) = (ConcreteCategory.hom (P.map g₂.op)) (x f₂ h₂)

Tactic:
k

Goal state after:
case mpr
C : Type u₁
inst✝ : Category.{v₁, u₁} C
P : Cᵒᵖ ⥤ Type w
X : C
S : Sieve X
x : FamilyOfElements P S.arrows
h : x.SieveCompatible
Y₁ Y₂ Z : C
g₁ : Z ⟶ Y₁
g₂ : Z ⟶ Y₂
f₁ : Y₁ ⟶ X
f₂ : Y₂ ⟶ X
h₁ : S.arrows f₁
h₂ : S.arrows f₂
k : g₁ ≫ f₁ = g₂ ≫ f₂
⊢ (ConcreteCategory.hom (P.map g₁.op)) (x f₁ h₁) = (ConcreteCategory.hom (P.map g₂.op)) (x f₂ h₂)
Module: Mathlib.CategoryTheory.Sites.Sieves

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
hX : IsTerminal X
I : Type u_1
Y : I → C
f : (i : I) → Y i ⟶ X
⊢ ofArrows Y f = ofObjects Y X

Tactic:
refine le_antisymm (ofArrows_le_ofObjects Y f) (fun W g => ?_)

Goal state after:
C : Type u₁
inst✝ : Category.{v₁, u₁} C
X : C
hX : IsTerminal X
I : Type u_1
Y : I → C
f : (i : I) → Y i ⟶ X
W : C
g : W ⟶ X
⊢ (ofObjects Y X).arrows g → (ofArrows Y f).arrows g
Module: Mathlib.CategoryTheory.Sites.EqualizerSheafCondition

Goal state before:
pp: case mpr
C : Type u
inst✝¹ : Category.{v, u} C
P : Cᵒᵖ ⥤ Type (max v u)
X : C
R : Presieve X
inst✝ : R.HasPairwisePullbacks
x : FirstObj P R
⊢ (ConcreteCategory.hom (firstMap P R)) x = (ConcreteCategory.hom (secondMap P R)) x →
    Presieve.FamilyOfElements.PullbackCompatible ((ConcreteCategory.hom (firstObjEqFamily P R).hom) x)

Tactic:
· intro t Y Z f g hf hg
    rw [Types.limit_ext_iff'] at t
    simpa [firstMap, secondMap] using t ⟨⟨⟨Y, f, hf⟩, Z, g, hg⟩⟩

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

Goal state before:
pp: C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
P Q U : Cᵒᵖ ⥤ Type w
X Y✝ : C
S : Sieve X
R : Presieve X
inst✝ : LocallySmall.{w, v₁, u₁} C
F : Cᵒᵖ ⥤ Type w
t : { x // x.Compatible }
Y Z : Cᵒᵖ
g : Y ⟶ Z
⊢ ((shrinkFunctor.{w, v₁, u₁} S).toFunctor.map g ≫ ↾fun f ↦ ↑t (shrinkYonedaObjObjEquiv ↑f) ⋯) =
    (↾fun f ↦ ↑t (shrinkYonedaObjObjEquiv ↑f) ⋯) ≫ F.map g

Tactic:
ext ⟨f, hf⟩

Goal state after:
C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
P Q U : Cᵒᵖ ⥤ Type w
X Y✝ : C
S : Sieve X
R : Presieve X
inst✝ : LocallySmall.{w, v₁, u₁} C
F : Cᵒᵖ ⥤ Type w
t : { x // x.Compatible }
Y Z : Cᵒᵖ
g : Y ⟶ Z
f : (shrinkYoneda.{w, v₁, u₁}.obj X).obj Y
hf : f ∈ (shrinkFunctor.{w, v₁, u₁} S).obj Y
⊢ (ConcreteCategory.hom
          ((shrinkFunctor.{w, v₁, u₁} S).toFunctor.map g ≫ ↾fun f ↦ ↑t (shrinkYonedaObjObjEquiv ↑f) ⋯)).toFun
      ⟨f, hf⟩ =
    (ConcreteCategory.hom ((↾fun f ↦ ↑t (shrinkYonedaObjObjEquiv ↑f) ⋯) ≫ F.map g)).toFun ⟨f, hf⟩
Module: Mathlib.CategoryTheory.Sites.Sheaf

Goal state before:
pp: C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
J : GrothendieckTopology C
A : Type u₂
inst✝ : Category.{v₂, u₂} A
X : A
hX : IsTerminal X
⊢ ∀ (X_1 : Sheaf J A) (m : X_1 ⟶ terminal J hX), m = { hom := (Functor.isTerminalConst Cᵒᵖ hX).from X_1.obj }

Tactic:
intros; ext; simpa using! hX.hom_ext _ _

Goal state after:
Module: Mathlib.CategoryTheory.Subfunctor.Image

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
F F' : C ⥤ Type w
G : Subfunctor F
p : F' ⟶ F
⊢ G.preimage p = ⊤ ↔ range p ≤ G

Tactic:
rw [← image_top, image_le_iff]
  simp

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

Goal state before:
pp: case refine_2
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) ⋯
hy✝ : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄ (hf : U.arrows f), (y✝ hf).Compatible
t : FamilyOfElements P U.arrows := fun Y f hf ↦ ⋯.amalgamate (y✝ hf) ⋯
ht : ∀ ⦃Y : C⦄ ⦃f : Y ⟶ X⦄ (hf : U.arrows f), (y✝ hf).IsAmalgamation (t f hf)
hT : t.Compatible
y : P.obj (op X)
hy : s.IsAmalgamation y
Y : C
f : Y ⟶ X
hf : U.arrows f
Z : C
g : Z ⟶ Y
hg : (B hf).arrows g
⊢ (ConcreteCategory.hom (P.map g.op)) ((ConcreteCategory.hom (P.map f.op)) y) =
    (ConcreteCategory.hom (P.map g.op)) ((ConcreteCategory.hom (P.map f.op)) (hU.amalgamate t hT))

Tactic:
rw [← comp_apply, ← Functor.map_comp, ← op_comp, hy _ (Presieve.bind_comp _ _ hg),
      hU.valid_glue _ _ hf, ht hf _ hg]

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

Goal state before:
pp: 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)
P : Cᵒᵖ ⥤ D
hsep :
  ∀ (X : C) (S : J.Cover X) (x y : ToType (P.obj (op X))),
    (∀ (I : S.Arrow), (ConcreteCategory.hom (P.map I.f.op)) x = (ConcreteCategory.hom (P.map I.f.op)) y) → x = y
X : C
S : J.Cover X
s : Meq (J.plusObj P) S
inj : ∀ (X : C), Function.Injective ⇑(ConcreteCategory.hom ((J.toPlus P).app (op X)))
T : (I : S.Arrow) → J.Cover I.Y
t : (I : S.Arrow) → Meq P (T I)
ht : ∀ (I : S.Arrow), ↑s I = mk (t I)
B : J.Cover X := S.bind T
⊢ ∃ t, Meq.mk S t = s

Tactic:
choose Z e1 e2 he2 _ _ using fun I : B.Arrow => I.hf

Goal state after:
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)
P : Cᵒᵖ ⥤ D
hsep :
  ∀ (X : C) (S : J.Cover X) (x y : ToType (P.obj (op X))),
    (∀ (I : S.Arrow), (ConcreteCategory.hom (P.map I.f.op)) x = (ConcreteCategory.hom (P.map I.f.op)) y) → x = y
X : C
S : J.Cover X
s : Meq (J.plusObj P) S
inj : ∀ (X : C), Function.Injective ⇑(ConcreteCategory.hom ((J.toPlus P).app (op X)))
T : (I : S.Arrow) → J.Cover I.Y
t : (I : S.Arrow) → Meq P (T I)
ht : ∀ (I : S.Arrow), ↑s I = mk (t I)
B : J.Cover X := S.bind T
Z : B.Arrow → C
e1 : (I : B.Arrow) → I.Y ⟶ Z I
e2 : (I : B.Arrow) → Z I ⟶ X
he2 : ∀ (I : B.Arrow), (↑S).arrows (e2 I)
h✝ :
  ∀ (I : B.Arrow),
    (fun x x_1 h ↦ ((fun Y f hf ↦ ↑(T { Y := Y, f := f, hf := hf })) x x_1 h).arrows) (Z I) (e2 I) ⋯ (e1 I)
a✝ : ∀ (I : B.Arrow), e1 I ≫ e2 I = I.f
⊢ ∃ t, Meq.mk S t = s
Module: Mathlib.CategoryTheory.Limits.ColimitLimit

Goal state before:
pp: J : Type u₁
K : Type u₂
inst✝⁴ : Category.{v₁, u₁} J
inst✝³ : Category.{v₂, u₂} K
C : Type u
inst✝² : Category.{v, u} C
F : J × K ⥤ C
inst✝¹ : HasLimitsOfShape J C
inst✝ : HasColimitsOfShape K C
j j' : J
f : j ⟶ j'
k : K
⊢ limit.π ((curry.obj (swap K J ⋙ F)).obj k) j' ≫ colimit.ι ((curry.obj F).obj j') k =
    limit.π ((curry.obj (swap K J ⋙ F)).obj k) j ≫
      ((curry.obj (swap K J ⋙ F)).obj k).map f ≫ colimit.ι ((curry.obj F).obj j') k

Tactic:
limit.w_assoc

Goal state after:
J : Type u₁
K : Type u₂
inst✝⁴ : Category.{v₁, u₁} J
inst✝³ : Category.{v₂, u₂} K
C : Type u
inst✝² : Category.{v, u} C
F : J × K ⥤ C
inst✝¹ : HasLimitsOfShape J C
inst✝ : HasColimitsOfShape K C
j j' : J
f : j ⟶ j'
k : K
⊢ limit.π ((curry.obj (swap K J ⋙ F)).obj k) j' ≫ colimit.ι ((curry.obj F).obj j') k =
    limit.π ((curry.obj (swap K J ⋙ F)).obj k) j' ≫ colimit.ι ((curry.obj F).obj j') k
Module: Mathlib.CategoryTheory.Sites.Limits

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
K : Type z
inst✝¹ : Category.{z', z} K
inst✝ : HasLimitsOfShape K D
F : K ⥤ Sheaf J D
E : Cone (F ⋙ sheafToPresheaf J D)
hE : IsLimit E
X : C
W : J.Cover X
S : Multifork (W.index E.pt)
i : W.shape.L
⊢ (isLimitOfPreserves ((evaluation Cᵒᵖ D).obj (op X)) hE).lift (multiforkEvaluationCone F E X W S) ≫
      (W.multifork E.pt).ι i =
    S.ι i

Tactic:
apply (isLimitOfPreserves ((evaluation Cᵒᵖ D).obj (op i.Y)) hE).hom_ext

Goal state after:
C : Type u
inst✝³ : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝² : Category.{w', w} D
K : Type z
inst✝¹ : Category.{z', z} K
inst✝ : HasLimitsOfShape K D
F : K ⥤ Sheaf J D
E : Cone (F ⋙ sheafToPresheaf J D)
hE : IsLimit E
X : C
W : J.Cover X
S : Multifork (W.index E.pt)
i : W.shape.L
⊢ ∀ (j : K),
    ((isLimitOfPreserves ((evaluation Cᵒᵖ D).obj (op X)) hE).lift (multiforkEvaluationCone F E X W S) ≫
          (W.multifork E.pt).ι i) ≫
        (((evaluation Cᵒᵖ D).obj (op i.Y)).mapCone E).π.app j =
      S.ι i ≫ (((evaluation Cᵒᵖ D).obj (op i.Y)).mapCone E).π.app j
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 : Cᵒᵖ ⥤ D
⊢ J.sheafifyMap (𝟙 P) = 𝟙 (J.sheafify P)

Tactic:
by
  dsimp [sheafifyMap, sheafify]
  simp

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 R : Cᵒᵖ ⥤ D
η : P ⟶ Q
γ : Q ⟶ R
⊢ J.sheafifyMap (η ≫ γ) = J.sheafifyMap η ≫ J.sheafifyMap γ

Tactic:
by
  dsimp [sheafifyMap, sheafify]
  simp

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

Goal state before:
pp: X Y Z : TopCat
f : X ⟶ Z
g : Y ⟶ Z
⊢ pullbackSnd f g = (pullbackIsoProdSubtype f g).inv ≫ pullback.snd f g

Tactic:
pullbackIsoProdSubtype_inv_snd

Goal state after:
X Y Z : TopCat
f : X ⟶ Z
g : Y ⟶ Z
⊢ pullbackSnd f g = pullbackSnd f g
Module: Mathlib.Topology.Category.TopCat.Limits.Products

Goal state before:
pp: case mp
X Y : TopCat
c : BinaryCofan X Y
h : IsColimit c
⊢ IsOpenEmbedding ⇑(ConcreteCategory.hom c.inl) ∧
    IsOpenEmbedding ⇑(ConcreteCategory.hom c.inr) ∧
      IsCompl (range ⇑(ConcreteCategory.hom c.inl)) (range ⇑(ConcreteCategory.hom c.inr))

Tactic:
rw [← show _ = c.inl from
          h.comp_coconePointUniqueUpToIso_inv (binaryCofanIsColimit X Y) ⟨WalkingPair.left⟩,
        ← show _ = c.inr from
          h.comp_coconePointUniqueUpToIso_inv (binaryCofanIsColimit X Y) ⟨WalkingPair.right⟩]

Goal state after:
case mp
X Y : TopCat
c : BinaryCofan X Y
h : IsColimit c
⊢ IsOpenEmbedding
      ⇑(ConcreteCategory.hom
          ((X.binaryCofan Y).ι.app { as := WalkingPair.left } ≫
            (h.coconePointUniqueUpToIso (X.binaryCofanIsColimit Y)).inv)) ∧
    IsOpenEmbedding
        ⇑(ConcreteCategory.hom
            ((X.binaryCofan Y).ι.app { as := WalkingPair.right } ≫
              (h.coconePointUniqueUpToIso (X.binaryCofanIsColimit Y)).inv)) ∧
      IsCompl
        (range
          ⇑(ConcreteCategory.hom
              ((X.binaryCofan Y).ι.app { as := WalkingPair.left } ≫
                (h.coconePointUniqueUpToIso (X.binaryCofanIsColimit Y)).inv)))
        (range
          ⇑(ConcreteCategory.hom
              ((X.binaryCofan Y).ι.app { as := WalkingPair.right } ≫
                (h.coconePointUniqueUpToIso (X.binaryCofanIsColimit Y)).inv)))
Module: Mathlib.Topology.Category.TopCat.Limits.Pullbacks

Goal state before:
pp: case isOpen_range
W X Y Z S T : TopCat
f₁ : W ⟶ S
f₂ : X ⟶ S
g₁ : Y ⟶ T
g₂ : Z ⟶ T
i₁ : W ⟶ Y
i₂ : X ⟶ Z
H₁ : IsOpenEmbedding ⇑(ConcreteCategory.hom i₁)
H₂ : IsOpenEmbedding ⇑(ConcreteCategory.hom i₂)
i₃ : S ⟶ T
H₃ : Mono i₃
eq₁ : f₁ ≫ i₃ = i₁ ≫ g₁
eq₂ : f₂ ≫ i₃ = i₂ ≫ g₂
⊢ IsOpen (Set.range ⇑(ConcreteCategory.hom (pullback.map f₁ f₂ g₁ g₂ i₁ i₂ i₃ eq₁ eq₂)))

Tactic:
range_pullback_map

Goal state after:
case isOpen_range
W X Y Z S T : TopCat
f₁ : W ⟶ S
f₂ : X ⟶ S
g₁ : Y ⟶ T
g₂ : Z ⟶ T
i₁ : W ⟶ Y
i₂ : X ⟶ Z
H₁ : IsOpenEmbedding ⇑(ConcreteCategory.hom i₁)
H₂ : IsOpenEmbedding ⇑(ConcreteCategory.hom i₂)
i₃ : S ⟶ T
H₃ : Mono i₃
eq₁ : f₁ ≫ i₃ = i₁ ≫ g₁
eq₂ : f₂ ≫ i₃ = i₂ ≫ g₂
⊢ IsOpen
    (⇑(ConcreteCategory.hom (pullback.fst g₁ g₂)) ⁻¹' Set.range ⇑(ConcreteCategory.hom i₁) ∩
      ⇑(ConcreteCategory.hom (pullback.snd g₁ g₂)) ⁻¹' Set.range ⇑(ConcreteCategory.hom i₂))
Module: Mathlib.CategoryTheory.Limits.VanKampen

Goal state before:
pp: J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
F G : J ⥤ C
α : F ⟶ G
inst✝ : IsIso α
c : Cocone G
hc : IsUniversalColimit c
F' : J ⥤ C
c' : Cocone F'
α' : F' ⟶ F
f : c'.pt ⟶ ((Cocone.precompose α).obj c).pt
e : α' ≫ ((Cocone.precompose α).obj c).ι = c'.ι ≫ (const J).map f
hα : NatTrans.Equifibered α'
H : ∀ (j : J), IsPullback (c'.ι.app j) (α'.app j) f (((Cocone.precompose α).obj c).ι.app j)
j : J
⊢ IsPullback (c'.ι.app j) ((α' ≫ α).app j) f (c.ι.app j)

Tactic:
simp only [NatTrans.comp_app]

Goal state after:
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
F G : J ⥤ C
α : F ⟶ G
inst✝ : IsIso α
c : Cocone G
hc : IsUniversalColimit c
F' : J ⥤ C
c' : Cocone F'
α' : F' ⟶ F
f : c'.pt ⟶ ((Cocone.precompose α).obj c).pt
e : α' ≫ ((Cocone.precompose α).obj c).ι = c'.ι ≫ (const J).map f
hα : NatTrans.Equifibered α'
H : ∀ (j : J), IsPullback (c'.ι.app j) (α'.app j) f (((Cocone.precompose α).obj c).ι.app j)
j : J
⊢ IsPullback (c'.ι.app j) (α'.app j ≫ α.app j) f (c.ι.app j)
Module: Mathlib.Topology.Category.TopCat.Limits.Products

Goal state before:
pp: case neg
X Y : TopCat
c : BinaryCofan X Y
h₁ : IsOpenEmbedding ⇑(ConcreteCategory.hom c.inl)
h₂ : IsOpenEmbedding ⇑(ConcreteCategory.hom c.inr)
h₃ : IsCompl (range ⇑(ConcreteCategory.hom c.inl)) (range ⇑(ConcreteCategory.hom c.inr))
this :
  ∀ (x : ↑(((Functor.const (Discrete WalkingPair)).obj c.pt).obj { as := WalkingPair.left })),
    x ∈ range ⇑(ConcreteCategory.hom c.inl) ∨ x ∈ range ⇑(ConcreteCategory.hom c.inr)
T : TopCat
f : X ⟶ T
g : Y ⟶ T
⊢ ContinuousOn
    (fun x ↦
      if h : x ∈ range ⇑(ConcreteCategory.hom c.inl) then
        (ConcreteCategory.hom f) ((Equiv.ofInjective ⇑(ConcreteCategory.hom c.inl) ⋯).symm ⟨x, ⋯⟩)
      else (ConcreteCategory.hom g) ((Equiv.ofInjective ⇑(ConcreteCategory.hom c.inr) ⋯).symm ⟨x, ⋯⟩))
    (range ⇑(ConcreteCategory.hom c.inl))ᶜ

pp: X Y : TopCat
c : BinaryCofan X Y
h₁ : IsOpenEmbedding ⇑(ConcreteCategory.hom c.inl)
h₂ : IsOpenEmbedding ⇑(ConcreteCategory.hom c.inr)
h₃ : IsCompl (range ⇑(ConcreteCategory.hom c.inl)) (range ⇑(ConcreteCategory.hom c.inr))
this :
  ∀ (x : ↑(((Functor.const (Discrete WalkingPair)).obj c.pt).obj { as := WalkingPair.left })),
    x ∈ range ⇑(ConcreteCategory.hom c.inl) ∨ x ∈ range ⇑(ConcreteCategory.hom c.inr)
T : TopCat
f : X ⟶ T
g : Y ⟶ T
⊢ IsOpen (range ⇑(ConcreteCategory.hom c.inl))ᶜ

Tactic:
· rw [continuousOn_iff_continuous_domRestrict]
            have : ∀ a, a ∉ Set.range c.inl → a ∈ Set.range c.inr := by
              rintro a (h : a ∈ (Set.range c.inl)ᶜ)
              rwa [eq_compl_iff_isCompl.mpr h₃.symm]
            convert_to! Continuous
                (g ∘ h₂.isEmbedding.toHomeomorph.symm ∘ Subtype.map _ this)
            · ext ⟨x, hx⟩
              exact dif_neg hx
            apply Continuous.comp
            · exact g.hom.continuous_toFun
            · apply Continuous.comp (by fun_prop)
              rw [IsEmbedding.subtypeVal.isInducing.continuous_iff]
              exact continuous_subtype_val

Goal state after:
X Y : TopCat
c : BinaryCofan X Y
h₁ : IsOpenEmbedding ⇑(ConcreteCategory.hom c.inl)
h₂ : IsOpenEmbedding ⇑(ConcreteCategory.hom c.inr)
h₃ : IsCompl (range ⇑(ConcreteCategory.hom c.inl)) (range ⇑(ConcreteCategory.hom c.inr))
this :
  ∀ (x : ↑(((Functor.const (Discrete WalkingPair)).obj c.pt).obj { as := WalkingPair.left })),
    x ∈ range ⇑(ConcreteCategory.hom c.inl) ∨ x ∈ range ⇑(ConcreteCategory.hom c.inr)
T : TopCat
f : X ⟶ T
g : Y ⟶ T
⊢ IsOpen (range ⇑(ConcreteCategory.hom c.inl))ᶜ
Module: Mathlib.CategoryTheory.Limits.MonoCoprod

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
I₁ : Type u_2
I₂ : Type u_3
X : I₁ ⊕ I₂ → C
c : Cofan X
c₁ : Cofan (X ∘ Sum.inl)
c₂ : Cofan (X ∘ Sum.inr)
hc : IsColimit c
hc₁ : IsColimit c₁
hc₂ : IsColimit c₂
inst✝ : MonoCoprod C
inl : c₁.pt ⟶ c.pt
hinl : ∀ (i₁ : I₁), c₁.inj i₁ ≫ inl = c.inj (Sum.inl i₁)
this : inl = (binaryCofanSum c c₁ c₂ hc₁ hc₂).inl
⊢ Mono inl

Tactic:
by
    rw [this]
    exact MonoCoprod.binaryCofan_inl _ (isColimitBinaryCofanSum c c₁ c₂ hc hc₁ hc₂)

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

Goal state before:
pp: case e'_2.mp
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
K : Type u_3
inst✝ : Category.{v_3, u_3} K
e : J ≌ K
F : K ⥤ C
c : Cocone F
hc : IsVanKampenColimit c
F' : J ⥤ C
c' : Cocone F'
α : F' ⟶ e.functor ⋙ F
f : c'.pt ⟶ (Cocone.whisker e.functor c).pt
e' : α ≫ (Cocone.whisker e.functor c).ι = c'.ι ≫ (const J).map f
hα : NatTrans.Equifibered α
H : ∀ (j : J), IsPullback (c'.ι.app j) (α.app j) f (c.ι.app (e.functor.obj j))
⊢ ∀ (j : K), IsPullback (c'.ι.app (e.inverse.obj j)) (α.app (e.inverse.obj j) ≫ F.map (e.counit.app j)) f (c.ι.app j)

Tactic:
k

Goal state after:
case e'_2.mp
J : Type v'
inst✝² : Category.{u', v'} J
C : Type u
inst✝¹ : Category.{v, u} C
K : Type u_3
inst✝ : Category.{v_3, u_3} K
e : J ≌ K
F : K ⥤ C
c : Cocone F
hc : IsVanKampenColimit c
F' : J ⥤ C
c' : Cocone F'
α : F' ⟶ e.functor ⋙ F
f : c'.pt ⟶ (Cocone.whisker e.functor c).pt
e' : α ≫ (Cocone.whisker e.functor c).ι = c'.ι ≫ (const J).map f
hα : NatTrans.Equifibered α
H : ∀ (j : J), IsPullback (c'.ι.app j) (α.app j) f (c.ι.app (e.functor.obj j))
k : K
⊢ IsPullback (c'.ι.app (e.inverse.obj k)) (α.app (e.inverse.obj k) ≫ F.map (e.counit.app k)) f (c.ι.app k)
Module: Mathlib.CategoryTheory.Limits.FilteredColimitCommutesFiniteLimit

Goal state before:
pp: J : Type u₁
K : Type u₂
inst✝⁴ : SmallCategory J
inst✝³ : Category.{v₂, u₂} K
inst✝² : Small.{v, u₂} K
inst✝¹ : FinCategory J
F : J × K ⥤ Type v
inst✝ : IsFiltered K
x : limit (curry.obj F ⋙ colim)
k : J → K
y : (j : J) → F.obj (j, k j)
e :
  ∀ (j : J),
    (ConcreteCategory.hom (colimit.ι ((curry.obj F).obj j) (k j))) (y j) =
      (ConcreteCategory.hom (limit.π (curry.obj F ⋙ colim) j)) x
k' : K
g : (j : J) → k j ⟶ k'
kf : {j j' : J} → (j ⟶ j') → K
gf hf : {j j' : J} → (f : j ⟶ j') → k' ⟶ kf f
wf :
  ∀ {j j' : J} (f : j ⟶ j'),
    (ConcreteCategory.hom (F.map (𝟙 j' ×ₘ g j' ≫ gf f))) (y j') = (ConcreteCategory.hom (F.map (f ×ₘ g j ≫ hf f))) (y j)
⊢ ∃ a, (ConcreteCategory.hom (colimitLimitToLimitColimit F)) a = x

Tactic:
(Tactic.tacticLet__
 "let"
 (Term.letConfig [])
 (Term.letDecl
  (Term.letIdDecl
   (Term.letId `O)
   []
   []
   ":="
   («term_∪_»
    (Term.paren
     (Term.hygienicLParen "(" (hygieneInfo `[anonymous]))
     (Term.app
      `Finset.univ.biUnion
      [(Term.fun
        "fun"
        (Term.basicFun
         [`j]
         []
         "=>"
         (Term.app
          `Finset.univ.biUnion
          [(Term.fun
            "fun"
            (Term.basicFun
             [`j']
             []
             "=>"
             (Term.app
              `Finset.univ.image
              [(Term.paren
                (Term.hygienicLParen "(" (hygieneInfo `[anonymous]))
                (Term.app (Term.explicit "@" `kf) [`j `j'])
                ")")])))])))])
     ")")
    "∪"
    (choice
     («term{_}» "{" [`k'] "}")
     (Term.structInst
      "{"
      []
      (Term.structInstFields [(Term.structInstField (Term.structInstLVal `k' []) [])])
      (Term.optEllipsis [])
      []
      "}"))))))

Goal state after:
J : Type u₁
K : Type u₂
inst✝⁴ : SmallCategory J
inst✝³ : Category.{v₂, u₂} K
inst✝² : Small.{v, u₂} K
inst✝¹ : FinCategory J
F : J × K ⥤ Type v
inst✝ : IsFiltered K
x : limit (curry.obj F ⋙ colim)
k : J → K
y : (j : J) → F.obj (j, k j)
e :
  ∀ (j : J),
    (ConcreteCategory.hom (colimit.ι ((curry.obj F).obj j) (k j))) (y j) =
      (ConcreteCategory.hom (limit.π (curry.obj F ⋙ colim) j)) x
k' : K
g : (j : J) → k j ⟶ k'
kf : {j j' : J} → (j ⟶ j') → K
gf hf : {j j' : J} → (f : j ⟶ j') → k' ⟶ kf f
wf :
  ∀ {j j' : J} (f : j ⟶ j'),
    (ConcreteCategory.hom (F.map (𝟙 j' ×ₘ g j' ≫ gf f))) (y j') = (ConcreteCategory.hom (F.map (f ×ₘ g j ≫ hf f))) (y j)
O : Finset K := (Finset.univ.biUnion fun j ↦ Finset.univ.biUnion fun j' ↦ Finset.image kf Finset.univ) ∪ {k'}
⊢ ∃ a, (ConcreteCategory.hom (colimitLimitToLimitColimit F)) a = x
Module: Mathlib.CategoryTheory.Adhesive.Basic

Goal state before:
pp: case mpr.uniq.h₁.h₁
C : Type u
inst✝ : Category.{v, u} C
X E Y YE : C
c : BinaryCofan X E
hc : IsColimit c
f : X ⟶ Y
iY : Y ⟶ YE
fE : c.pt ⟶ YE
H✝ : CommSq f c.inl iY fE
H : IsPushout f c.inl iY fE
s : BinaryCofan ((pair X E).obj { as := WalkingPair.right }) Y
m : YE ⟶ s.pt
e₁ : (c.inr ≫ fE) ≫ m = s.inl
e₂ : iY ≫ m = s.inr
⊢ c.inl ≫ H.cocone.inr ≫ m = (BinaryCofan.mk (f ≫ s.inr) s.inl).ι.app { as := WalkingPair.left }

Tactic:
erw [← H.w_assoc]

Goal state after:
case mpr.uniq.h₁.h₁
C : Type u
inst✝ : Category.{v, u} C
X E Y YE : C
c : BinaryCofan X E
hc : IsColimit c
f : X ⟶ Y
iY : Y ⟶ YE
fE : c.pt ⟶ YE
H✝ : CommSq f c.inl iY fE
H : IsPushout f c.inl iY fE
s : BinaryCofan ((pair X E).obj { as := WalkingPair.right }) Y
m : YE ⟶ s.pt
e₁ : (c.inr ≫ fE) ≫ m = s.inl
e₂ : iY ≫ m = s.inr
⊢ f ≫ iY ≫ m = (BinaryCofan.mk (f ≫ s.inr) s.inl).ι.app { as := WalkingPair.left }