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

Goal state before:
pp: case e_a
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)
P : Cᵒᵖ ⥤ D
inst✝ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
X Y Z : Cᵒᵖ
f : X ⟶ Y
g : Y ⟶ Z
S : (J.Cover (unop X))ᵒᵖ
e : (unop S).pullback (g.unop ≫ f.unop) ≅ ((unop S).pullback f.unop).pullback g.unop :=
  (unop S).pullbackComp g.unop f.unop
I : (unop (op (((unop S).pullback f.unop).pullback g.unop))).shape.L
⊢ Multiequalizer.ι ((unop S).index P) (Cover.Arrow.map I e.inv).base =
    Multiequalizer.ι ((unop S).index P) (Cover.Arrow.base I).base

Tactic:
cases I

Goal state after:
case e_a.mk
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)
P : Cᵒᵖ ⥤ D
inst✝ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
X Y Z : Cᵒᵖ
f : X ⟶ Y
g : Y ⟶ Z
S : (J.Cover (unop X))ᵒᵖ
e : (unop S).pullback (g.unop ≫ f.unop) ≅ ((unop S).pullback f.unop).pullback g.unop :=
  (unop S).pullbackComp g.unop f.unop
Y✝ : C
f✝ : Y✝ ⟶ unop Z
hf✝ : (↑(unop (op (((unop S).pullback f.unop).pullback g.unop)))).arrows f✝
⊢ Multiequalizer.ι ((unop S).index P) ({ Y := Y✝, f := f✝, hf := hf✝ }.map e.inv).base =
    Multiequalizer.ι ((unop S).index P) { Y := Y✝, f := f✝, hf := hf✝ }.base.base
Module: Mathlib.CategoryTheory.Sites.Sheaf

Goal state before:
pp: C : Type u₁
inst✝³ : Category.{v₁, u₁} C
A : Type u₂
inst✝² : Category.{v₂, u₂} A
A' : Type u₂
inst✝¹ : Category.{max v₁ u₁, u₂} A'
B : Type u₃
inst✝ : Category.{v₃, u₃} B
J : GrothendieckTopology C
U : C
R : Presieve U
P : Cᵒᵖ ⥤ A
P' : Cᵒᵖ ⥤ A'
hP : ∀ (X : C) (S : J.Cover X), Nonempty (IsLimit (S.multifork P))
X : C
S : J.Cover X
⊢ IsLimit (S.multifork P)

Tactic:
exact (hP X S).some

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

Goal state before:
pp: case e'_2
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
h : mk x = mk y
W : (J.Cover X)ᵒᵖ
h1 : op S ⟶ W
h2 : op T ⟶ W
I : (unop W).Arrow
hh :
  (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) I))
      ((ConcreteCategory.hom ((J.diagram P X).map h1)) ((Meq.equiv P S).symm x)) =
    (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) I))
      ((ConcreteCategory.hom ((J.diagram P X).map h2)) ((Meq.equiv P T).symm y))
e_1✝ : ToType (P.obj (op I.Y)) = CD (((unop W).index P).left I)
⊢ ↑x { Y := I.Y, f := I.f, hf := ⋯ } = ↑x (I.map h1.unop)

Tactic:
cases I

Goal state after:
case e'_2.mk
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
h : mk x = mk y
W : (J.Cover X)ᵒᵖ
h1 : op S ⟶ W
h2 : op T ⟶ W
Y✝ : C
f✝ : Y✝ ⟶ X
hf✝ : (↑(unop W)).arrows f✝
hh :
  (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) { Y := Y✝, f := f✝, hf := hf✝ }))
      ((ConcreteCategory.hom ((J.diagram P X).map h1)) ((Meq.equiv P S).symm x)) =
    (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) { Y := Y✝, f := f✝, hf := hf✝ }))
      ((ConcreteCategory.hom ((J.diagram P X).map h2)) ((Meq.equiv P T).symm y))
e_1✝ :
  ToType (P.obj (op { Y := Y✝, f := f✝, hf := hf✝ }.Y)) = CD (((unop W).index P).left { Y := Y✝, f := f✝, hf := hf✝ })
⊢ ↑x { Y := { Y := Y✝, f := f✝, hf := hf✝ }.Y, f := { Y := Y✝, f := f✝, hf := hf✝ }.f, hf := ⋯ } =
    ↑x ({ Y := Y✝, f := f✝, hf := hf✝ }.map h1.unop)
Module: Mathlib.CategoryTheory.Subfunctor.Image

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

Tactic:
range_ι,

Goal state after:
C : Type u
inst✝ : Category.{v, u} C
F F' F'' : C ⥤ Type w
G : Subfunctor F
p : F' ⟶ F
⊢ (G.preimage p).image p ≤ G
Module: Mathlib.CategoryTheory.Sites.ConcreteSheafification

Goal state before:
pp: case e'_3
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
h : mk x = mk y
W : (J.Cover X)ᵒᵖ
h1 : op S ⟶ W
h2 : op T ⟶ W
I : (unop W).Arrow
hh :
  (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) I))
      ((ConcreteCategory.hom ((J.diagram P X).map h1)) ((Meq.equiv P S).symm x)) =
    (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) I))
      ((ConcreteCategory.hom ((J.diagram P X).map h2)) ((Meq.equiv P T).symm y))
e_1✝ : ToType (P.obj (op I.Y)) = CD (((unop W).index P).left I)
⊢ ↑y { Y := I.Y, f := I.f, hf := ⋯ } = ↑y (I.map h2.unop)

Tactic:
cases I

Goal state after:
case e'_3.mk
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
h : mk x = mk y
W : (J.Cover X)ᵒᵖ
h1 : op S ⟶ W
h2 : op T ⟶ W
Y✝ : C
f✝ : Y✝ ⟶ X
hf✝ : (↑(unop W)).arrows f✝
hh :
  (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) { Y := Y✝, f := f✝, hf := hf✝ }))
      ((ConcreteCategory.hom ((J.diagram P X).map h1)) ((Meq.equiv P S).symm x)) =
    (ConcreteCategory.hom (Multiequalizer.ι ((unop W).index P) { Y := Y✝, f := f✝, hf := hf✝ }))
      ((ConcreteCategory.hom ((J.diagram P X).map h2)) ((Meq.equiv P T).symm y))
e_1✝ :
  ToType (P.obj (op { Y := Y✝, f := f✝, hf := hf✝ }.Y)) = CD (((unop W).index P).left { Y := Y✝, f := f✝, hf := hf✝ })
⊢ ↑y { Y := { Y := Y✝, f := f✝, hf := hf✝ }.Y, f := { Y := Y✝, f := f✝, hf := hf✝ }.f, hf := ⋯ } =
    ↑y ({ Y := Y✝, f := f✝, hf := hf✝ }.map h2.unop)
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 := ⋯
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
w : Meq P B := ⋯
I : S.Arrow
II : (T I).Arrow
Y : C
f : Y ⟶ II.Y
hf : (↑((J.pullback II.f).obj (T I))).arrows f
⊢ (↑(T { Y := I.Y, f := I.f, hf := ⋯ })).arrows (f ≫ II.f)

Tactic:
cases I

Goal state after:
case mk
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
w : Meq P B := meqOfSep P hsep X S s T t ht
Y Y✝ : C
f✝ : Y✝ ⟶ X
hf✝ : (↑S).arrows f✝
II : (T { Y := Y✝, f := f✝, hf := hf✝ }).Arrow
f : Y ⟶ II.Y
hf : (↑((J.pullback II.f).obj (T { Y := Y✝, f := f✝, hf := hf✝ }))).arrows f
⊢ (↑(T { Y := { Y := Y✝, f := f✝, hf := hf✝ }.Y, f := { Y := Y✝, f := f✝, hf := hf✝ }.f, hf := ⋯ })).arrows (f ≫ II.f)
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✝ : HasWeakSheafify J D
F : K ⥤ Sheaf J D
E : Cocone (F ⋙ sheafToPresheaf J D)
k : K
⊢ ((presheafToSheaf J D).map (E.ι.app k)).hom =
    sheafifyLift J (𝟙 (F.obj k).obj) ⋯ ≫ toSheafify J (F.obj k).obj ≫ sheafifyMap J (E.ι.app k)

Tactic:
sheafifyLift_id_toSheafify_assoc

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✝ : HasWeakSheafify J D
F : K ⥤ Sheaf J D
E : Cocone (F ⋙ sheafToPresheaf J D)
k : K
⊢ ((presheafToSheaf J D).map (E.ι.app k)).hom = sheafifyMap J (E.ι.app k)
Module: Mathlib.Topology.Category.TopCat.Limits.Products

Goal state before:
pp: case refine_2
J : Type v
inst✝ : Category.{w, v} J
ι : Type v
α : ι → TopCat
i : ι
⊢ Continuous (Sigma.mk i)

Tactic:
continuity

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

Goal state before:
pp: J : Type v
inst✝ : Category.{w, v} J
ι : Type v
β : ι → TopCat
S : Cocone (Discrete.functor β)
⊢ Continuous fun s ↦ (ConcreteCategory.hom (S.ι.app { as := s.fst })) s.snd

Tactic:
continuity

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

Goal state before:
pp: case refine_2
X Y : TopCat
f g : X ⟶ Y
c : Cofork f g
hc : IsColimit c
⊢ Function.Surjective ⇑(ConcreteCategory.hom c.π)

Tactic:
· simpa only [← epi_iff_surjective] using epi_of_isColimit_cofork hc

Goal state after:
Module: Mathlib.CategoryTheory.Limits.Shapes.DisjointCoproduct

Goal state before:
pp: case refine_2
C : Type u
inst✝¹ : Category.{v, u} C
ι : Type u_1
X : ι → C
c : Cofan X
hc : IsColimit c
inst✝ : ∀ (i : ι), Mono (c.inj i)
s : {i j : ι} → i ≠ j → PullbackCone (c.inj i) (c.inj j)
hs : {i j : ι} → (hij : i ≠ j) → IsLimit (s hij)
H : {i j : ι} → (hij : i ≠ j) → IsInitial (s hij).pt
d : Cofan X
hd : IsColimit d
i j : ι
hij : i ≠ j
t : PullbackCone (d.inj i) (d.inj j)
ht : IsLimit t
e : d ≅ c := hd.uniqueUpToIso hc
heq : ∀ (i : ι), d.inj i ≫ e.hom.hom = c.inj i
u : t.pt ⟶ (s hij).pt := PullbackCone.IsLimit.lift (hs hij) t.fst t.snd ⋯
⊢ (u ≫ (H hij).to t.pt) ≫ t.snd = 𝟙 t.pt ≫ t.snd

Tactic:
simp [show (H hij).to (X j) = (s hij).snd from (H hij).hom_ext _ _, u]

Goal state after:
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: J : Type v'
inst✝⁴ : Category.{u', v'} J
C : Type u
inst✝³ : Category.{v, u} C
D : Type u''
inst✝² : Category.{v'', u''} D
X✝ Y✝ : C
inst✝¹ : HasBinaryCoproducts C
inst✝ : HasPullbacksOfInclusions C
X Y Z : C
f : Z ⟶ X ⨿ Y
⊢ HasPullback f coprod.inr

Tactic:
by
  have : IsPullback (𝟙 _) (f ≫ (coprod.braiding X Y).hom) f (coprod.braiding Y X).hom :=
    IsPullback.of_horiz_isIso ⟨by simp⟩
  have := (IsPullback.of_hasPullback (f ≫ (coprod.braiding X Y).hom) coprod.inl).paste_horiz this
  simp only [coprod.braiding_hom, Category.comp_id, colimit.ι_desc,
    BinaryCofan.ι_app_left, BinaryCofan.mk_inl] at this
  exact ⟨⟨⟨_, this.isLimit⟩⟩⟩

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

Goal state before:
pp: case mp
C : Type u
inst✝ : Category.{v, u} C
W X Y Z : C
f : W ⟶ X
g : W ⟶ Y
h : X ⟶ Z
i : Y ⟶ Z
H✝ : IsPushout f g h i
H : H✝.IsVanKampen
F' : WalkingSpan ⥤ C
c' : Cocone F'
α : F' ⟶ span f g
⊢ ∀ (f_1 : c'.pt ⟶ (PushoutCocone.mk h i ⋯).pt),
    α ≫ (PushoutCocone.mk h i ⋯).ι = c'.ι ≫ (Functor.const WalkingSpan).map f_1 →
      NatTrans.Equifibered α →
        (Nonempty (IsColimit c') ↔
          ∀ (j : WalkingSpan), IsPullback (c'.ι.app j) (α.app j) f_1 ((PushoutCocone.mk h i ⋯).ι.app j))

Tactic:
fα

Goal state after:
case mp
C : Type u
inst✝ : Category.{v, u} C
W X Y Z : C
f : W ⟶ X
g : W ⟶ Y
h : X ⟶ Z
i : Y ⟶ Z
H✝ : IsPushout f g h i
H : H✝.IsVanKampen
F' : WalkingSpan ⥤ C
c' : Cocone F'
α : F' ⟶ span f g
fα : c'.pt ⟶ (PushoutCocone.mk h i ⋯).pt
⊢ α ≫ (PushoutCocone.mk h i ⋯).ι = c'.ι ≫ (Functor.const WalkingSpan).map fα →
    NatTrans.Equifibered α →
      (Nonempty (IsColimit c') ↔
        ∀ (j : WalkingSpan), IsPullback (c'.ι.app j) (α.app j) fα ((PushoutCocone.mk h i ⋯).ι.app j))
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: case refine_2
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
Z : TopCat
f : Z ⟶ TopCat.of (PUnit.{u + 1} ⊕ PUnit.{u + 1})
h₁ :
  Set.range
      ⇑(ConcreteCategory.hom
          (TopCat.pullbackFst f ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inl)) =
    ⇑(ConcreteCategory.hom f) ⁻¹' Set.range Sum.inl
h₂ :
  Set.range
      ⇑(ConcreteCategory.hom
          (TopCat.pullbackFst f ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inr)) =
    ⇑(ConcreteCategory.hom f) ⁻¹' Set.range Sum.inr
⊢ IsOpen
    (Set.range
      ⇑(ConcreteCategory.hom
          (BinaryCofan.mk (TopCat.pullbackFst f ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inl)
              (TopCat.pullbackFst f ((TopCat.of PUnit.{u + 1}).binaryCofan (TopCat.of PUnit.{u + 1})).inr)).inr))

Tactic:
convert! f.hom.2.1 _ isOpen_range_inr

Goal state after:
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: case succ
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : FinitaryExtensive C
n : ℕ
IH : ∀ (f : Fin n → C) {c : Cocone (Discrete.functor f)} (hc : IsColimit c), IsVanKampenColimit c
f : Fin (n + 1) → C
c : Cocone (Discrete.functor f)
hc : IsColimit c
⊢ IsVanKampenColimit c

Tactic:
apply IsVanKampenColimit.of_iso _
      ((extendCofanIsColimit f (coproductIsCoproduct _) (coprodIsCoprod _ _)).uniqueUpToIso hc)

Goal state after:
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : FinitaryExtensive C
n : ℕ
IH : ∀ (f : Fin n → C) {c : Cocone (Discrete.functor f)} (hc : IsColimit c), IsVanKampenColimit c
f : Fin (n + 1) → C
c : Cocone (Discrete.functor f)
hc : IsColimit c
⊢ IsVanKampenColimit
    (extendCofan (Cofan.mk (∐ fun i ↦ f i.succ) (Sigma.ι fun i ↦ f i.succ)) (BinaryCofan.mk coprod.inl coprod.inr))
Module: Mathlib.CategoryTheory.ObjectProperty.Local

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
W W' : MorphismProperty C
J : Type u'
inst✝ : Category.{v', u'} J
Z : C
x✝ : W.isLocal.limitsOfShape J Z
X Y : C
f : X ⟶ Y
hf : W f
p : W.isLocal.LimitOfShape J Z
g : X ⟶ Z
⊢ ∃ a, (fun g ↦ f ≫ g) a = g

Tactic:
choose app h using fun j ↦ (p.prop_diag_obj j f hf).2 (g ≫ p.π.app j)

Goal state after:
C : Type u
inst✝¹ : Category.{v, u} C
W W' : MorphismProperty C
J : Type u'
inst✝ : Category.{v', u'} J
Z : C
x✝ : W.isLocal.limitsOfShape J Z
X Y : C
f : X ⟶ Y
hf : W f
p : W.isLocal.LimitOfShape J Z
g : X ⟶ Z
app : (j : J) → Y ⟶ p.diag.obj j
h : ∀ (j : J), (fun g ↦ f ≫ g) (app j) = g ≫ p.π.app j
⊢ ∃ a, (fun g ↦ f ≫ g) a = g
Module: Mathlib.CategoryTheory.Localization.Bousfield

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝³ : Category.{v_1, u_1} C
inst✝² : Category.{v_2, u_2} D
F : C ⥤ D
G : D ⥤ C
adj : G ⊣ F
inst✝¹ : G.Full
inst✝ : G.Faithful
X Y : C
f : X ⟶ Y
⊢ isColocal (fun x ↦ x ∈ Set.range G.obj) f ↔ IsIso (F.map f)

Tactic:
by
  have := adj.counit.naturality f
  dsimp at this
  rw [← (isColocal _).precomp_iff _ _ (isColocal_adj_counit_app adj X),
    ← this, (isColocal _).postcomp_iff _ _ (isColocal_adj_counit_app adj Y),
    isColocal_iff_isIso _ _ ⟨_, rfl⟩ ⟨_, rfl⟩]
  exact ⟨fun _ ↦ isIso_of_fully_faithful G (F.map f), fun _ ↦ inferInstance⟩

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

Goal state before:
pp: case refine_2
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : HasInitial C
X Y : C
c : BinaryCofan X Y
h : IsVanKampenColimit c
⊢ IsColimit (BinaryCofan.mk (initial.to Y) (𝟙 Y))

Tactic:
exact ((BinaryCofan.isColimit_iff_isIso_inr initialIsInitial _).mpr (by
      dsimp
      infer_instance)).some

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

Goal state before:
pp: case refine_2
C : Type u
inst✝¹ : Category.{v, u} C
X Y : C
inst✝ : HasInitial C
c : BinaryCofan X Y
h : IsVanKampenColimit c
⊢ IsColimit (BinaryCofan.mk (initial.to Y) (𝟙 Y))

Tactic:
exact ((BinaryCofan.isColimit_iff_isIso_inr initialIsInitial _).mpr (by
      dsimp
      infer_instance)).some

Goal state after:
Module: Mathlib.Algebra.Category.ModuleCat.Presheaf.Submodule

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v₁, u₁} C
R : Cᵒᵖ ⥤ RingCat
M : PresheafOfModules R
N : M.Submodule
s : Set M.Submodule
X✝ Y✝ : Cᵒᵖ
f : X✝ ⟶ Y✝
⊢ ⨅ N ∈ s, N.obj X✝ ≤ Submodule.comap (M.restrictₛₗ f) (⨅ N ∈ s, N.obj Y✝)

Tactic:
simp_rw [Submodule.comap_iInf, le_iInf₂_iff]
        intro N hN
        refine iInf₂_le_of_le _ hN (N.map _)

Goal state after:
Module: Mathlib.CategoryTheory.Abelian.Projective.Dimension

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Abelian C
X : C
n : ℕ
h : HasProjectiveDimensionLT X (n + 1)
⊢ ↑n < ↑(n + 1)

Tactic:
by simp [ENat.WithBot.lt_add_one_iff]

Goal state after:
Module: Mathlib.Algebra.Category.ModuleCat.Presheaf.Sheafify

Goal state before:
pp: C : Type u₁
inst✝⁷ : Category.{v₁, u₁} C
J : GrothendieckTopology C
R₀ : Cᵒᵖ ⥤ RingCat
R : Sheaf J RingCat
α : R₀ ⟶ R.obj
inst✝⁶ : Presheaf.IsLocallyInjective J α
inst✝⁵ : Presheaf.IsLocallySurjective J α
M₀ : PresheafOfModules R₀
A : Sheaf J AddCommGrpCat
φ : M₀.presheaf ⟶ A.obj
inst✝⁴ : Presheaf.IsLocallyInjective J φ
inst✝³ : Presheaf.IsLocallySurjective J φ
inst✝² : J.WEqualsLocallyBijective AddCommGrpCat
M₀' : PresheafOfModules R₀
A' : Sheaf J AddCommGrpCat
φ' : M₀'.presheaf ⟶ A'.obj
inst✝¹ : Presheaf.IsLocallyInjective J φ'
inst✝ : Presheaf.IsLocallySurjective J φ'
τ₀ : M₀ ⟶ M₀'
τ : A ⟶ A'
fac : (toPresheaf R₀).map τ₀ ≫ φ' = φ ≫ τ.hom
X : Cᵒᵖ
r : ↑(R.obj.obj X)
m : ↑((sheafify α φ).val.obj X)
f : (sheafify α φ).val ⟶ (sheafify α φ').val := (sheafifyHomEquiv' α φ ⋯).symm (τ₀ ≫ toSheafify α φ')
⊢ (ConcreteCategory.hom (τ.hom.app X)) (r • m) = r • (ConcreteCategory.hom (τ.hom.app X)) m

Tactic:
suffices τ.hom = (toPresheaf _).map f by simpa only [this] using! (f.app X).hom.map_smul r m

Goal state after:
C : Type u₁
inst✝⁷ : Category.{v₁, u₁} C
J : GrothendieckTopology C
R₀ : Cᵒᵖ ⥤ RingCat
R : Sheaf J RingCat
α : R₀ ⟶ R.obj
inst✝⁶ : Presheaf.IsLocallyInjective J α
inst✝⁵ : Presheaf.IsLocallySurjective J α
M₀ : PresheafOfModules R₀
A : Sheaf J AddCommGrpCat
φ : M₀.presheaf ⟶ A.obj
inst✝⁴ : Presheaf.IsLocallyInjective J φ
inst✝³ : Presheaf.IsLocallySurjective J φ
inst✝² : J.WEqualsLocallyBijective AddCommGrpCat
M₀' : PresheafOfModules R₀
A' : Sheaf J AddCommGrpCat
φ' : M₀'.presheaf ⟶ A'.obj
inst✝¹ : Presheaf.IsLocallyInjective J φ'
inst✝ : Presheaf.IsLocallySurjective J φ'
τ₀ : M₀ ⟶ M₀'
τ : A ⟶ A'
fac : (toPresheaf R₀).map τ₀ ≫ φ' = φ ≫ τ.hom
X : Cᵒᵖ
r : ↑(R.obj.obj X)
m : ↑((sheafify α φ).val.obj X)
f : (sheafify α φ).val ⟶ (sheafify α φ').val := (sheafifyHomEquiv' α φ ⋯).symm (τ₀ ≫ toSheafify α φ')
⊢ τ.hom = (toPresheaf R.obj).map f
Module: Mathlib.CategoryTheory.Sites.Closed

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
J₁ : GrothendieckTopology C
⊢ topologyOfClosureOperator J₁.closureOperator ⋯ = J₁

Tactic:
ext X S
  apply GrothendieckTopology.close_eq_top_iff_mem

Goal state after:
Module: Mathlib.CategoryTheory.Sites.Hypercover.Zero

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
S : C
E : PreZeroHypercover S
F : PreZeroHypercover S
f : E.Hom F
i : E.I₀
⊢ F.sieve₀.arrows (f.h₀ i ≫ F.f (f.s₀ i))

Tactic:
apply Sieve.downward_closed

Goal state after:
C : Type u
inst✝ : Category.{v, u} C
S : C
E : PreZeroHypercover S
F : PreZeroHypercover S
f : E.Hom F
i : E.I₀
⊢ F.sieve₀.arrows (F.f (f.s₀ i))
Module: Mathlib.CategoryTheory.Sites.Hypercover.Zero

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
S : C
E F : PreZeroHypercover S
h : E.shrink = F.shrink
⊢ E.presieve₀ = F.presieve₀

Tactic:
← E.presieve₀_shrink,

Goal state after:
C : Type u
inst✝ : Category.{v, u} C
S : C
E F : PreZeroHypercover S
h : E.shrink = F.shrink
⊢ E.shrink.presieve₀ = F.presieve₀