mathlib-initiative/mathlib-tactics huggingface dataset:
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))
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)

Tactic:
rw [← Category.comp_id f]

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 ≫ 𝟙 (Cocone.whisker e.functor c).pt) (c.ι.app k)
Module: Mathlib.CategoryTheory.Extensive

Goal state before:
pp: J : Type v'
inst✝⁵ : Category.{u', v'} J
C : Type u
inst✝⁴ : Category.{v, u} C
D✝ : Type u''
inst✝³ : Category.{v'', u''} D✝
X✝ Y✝ : C
D : Type u_1
inst✝² : Category.{v_1, u_1} D
inst✝¹ : HasBinaryCoproducts C
F : C ⥤ D
inst✝ : PreservesPullbacksOfInclusions F
X Y Z : C
f : Z ⟶ X ⨿ Y
⊢ cospan (f ≫ (coprod.braiding X Y).hom) coprod.inl ≅ cospan f coprod.inr

Tactic:
apply cospanExt (Iso.refl _) (Iso.refl _) (coprod.braiding X Y).symm

Goal state after:
case wf
J : Type v'
inst✝⁵ : Category.{u', v'} J
C : Type u
inst✝⁴ : Category.{v, u} C
D✝ : Type u''
inst✝³ : Category.{v'', u''} D✝
X✝ Y✝ : C
D : Type u_1
inst✝² : Category.{v_1, u_1} D
inst✝¹ : HasBinaryCoproducts C
F : C ⥤ D
inst✝ : PreservesPullbacksOfInclusions F
X Y Z : C
f : Z ⟶ X ⨿ Y
⊢ (Iso.refl Z).hom ≫ f = (f ≫ (coprod.braiding X Y).hom) ≫ (coprod.braiding X Y).symm.hom

case wg
J : Type v'
inst✝⁵ : Category.{u', v'} J
C : Type u
inst✝⁴ : Category.{v, u} C
D✝ : Type u''
inst✝³ : Category.{v'', u''} D✝
X✝ Y✝ : C
D : Type u_1
inst✝² : Category.{v_1, u_1} D
inst✝¹ : HasBinaryCoproducts C
F : C ⥤ D
inst✝ : PreservesPullbacksOfInclusions F
X Y Z : C
f : Z ⟶ X ⨿ Y
⊢ (Iso.refl Y).hom ≫ coprod.inr = coprod.inl ≫ (coprod.braiding X Y).symm.hom
Module: Mathlib.CategoryTheory.Adhesive.Basic

Goal state before:
pp: case mpr.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' :
  ∀ ⦃X' Y' Z' : C⦄ (h' : X' ⟶ Z') (i' : Y' ⟶ Z') (αX : X' ⟶ X) (αY : Y' ⟶ Y) (αZ : Z' ⟶ Z),
    CommSq h' αX αZ h →
      CommSq i' αY αZ i →
        ∀ [HasPullback αX f],
          IsPullback h' αX αZ h ∧ IsPullback i' αY αZ i ↔
            ∃ W' f' g' αW, IsPullback f' αW αX f ∧ IsPullback g' αW αY g ∧ IsPushout f' g' h' i'
W' X' Y' Z' : C
f' : W' ⟶ X'
g' : W' ⟶ Y'
h' : X' ⟶ Z'
i' : Y' ⟶ Z'
αW : W' ⟶ W
αX : X' ⟶ X
αY : Y' ⟶ Y
αZ : Z' ⟶ Z
hf : IsPullback f' αW αX f
hg : IsPullback g' αW αY g
sq_h : CommSq h' αX αZ h
sq_i : CommSq i' αY αZ i
cs : CommSq f' g' h' i'
this : HasPullback αX f := ⋯
⊢ IsPushout f' g' h' i' → IsPullback h' αX αZ h ∧ IsPullback i' αY αZ i

Tactic:
intro H''

Goal state after:
case mpr.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' :
  ∀ ⦃X' Y' Z' : C⦄ (h' : X' ⟶ Z') (i' : Y' ⟶ Z') (αX : X' ⟶ X) (αY : Y' ⟶ Y) (αZ : Z' ⟶ Z),
    CommSq h' αX αZ h →
      CommSq i' αY αZ i →
        ∀ [HasPullback αX f],
          IsPullback h' αX αZ h ∧ IsPullback i' αY αZ i ↔
            ∃ W' f' g' αW, IsPullback f' αW αX f ∧ IsPullback g' αW αY g ∧ IsPushout f' g' h' i'
W' X' Y' Z' : C
f' : W' ⟶ X'
g' : W' ⟶ Y'
h' : X' ⟶ Z'
i' : Y' ⟶ Z'
αW : W' ⟶ W
αX : X' ⟶ X
αY : Y' ⟶ Y
αZ : Z' ⟶ Z
hf : IsPullback f' αW αX f
hg : IsPullback g' αW αY g
sq_h : CommSq h' αX αZ h
sq_i : CommSq i' αY αZ i
cs : CommSq f' g' h' i'
this : HasPullback αX f := IsPullback.hasPullback hf
H'' : IsPushout f' g' h' i'
⊢ IsPullback h' αX αZ h ∧ IsPullback i' αY αZ i
Module: Mathlib.CategoryTheory.Adhesive.Basic

Goal state before:
pp: case mp.refine_1.h₂
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 : IsColimit (BinaryCofan.mk (c.inr ≫ fE) iY)
s : PushoutCocone f c.inl
⊢ (c.inr ≫ fE) ≫ BinaryCofan.IsColimit.desc h (c.inr ≫ s.inr) s.inl = c.inr ≫ s.inr

Tactic:
exact h.fac _ ⟨WalkingPair.left⟩

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

Goal state before:
pp: case mp.refine_2.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 : IsColimit (BinaryCofan.mk (c.inr ≫ fE) iY)
s : PushoutCocone f c.inl
m : (PushoutCocone.mk iY fE ⋯).pt ⟶ s.pt
e₁ : iY ≫ m = s.inl
e₂ : fE ≫ m = s.inr
⊢ (c.inr ≫ fE) ≫ BinaryCofan.IsColimit.desc h (c.inr ≫ s.inr) s.inl = c.inr ≫ s.inr

Tactic:
exact h.fac _ ⟨WalkingPair.left⟩

Goal state after:
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)
k'' : K
i : {j j' : J} → (f : j ⟶ j') → kf f ⟶ k''
s : ∀ {j₁ j₂ j₃ j₄ : J} (f : j₁ ⟶ j₂) (f' : j₃ ⟶ j₄), gf f ≫ i f = hf f' ≫ i f'
j j' : J
f : j ⟶ j'
⊢ (ConcreteCategory.hom (F.map (𝟙 j' ×ₘ g j' ≫ gf f ≫ i f))) (y j') =
    (ConcreteCategory.hom (F.map (𝟙 j' ×ₘ g j' ≫ gf (𝟙 j') ≫ i (𝟙 j')))) (y j')

Tactic:
by
            rw [s f (𝟙 j'), ← s (𝟙 j') (𝟙 j')]

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

Goal state before:
pp: J : Type v'
inst✝⁴ : Category.{u', v'} J
C : Type u
inst✝³ : Category.{v, u} C
W X Y Z✝ : C
f✝ : W ⟶ X
g✝ : W ⟶ Y
h : X ⟶ Z✝
i : Y ⟶ Z✝
inst✝² : Adhesive C
Z A B : C
a : A ⟶ Z
b : B ⟶ Z
inst✝¹ : Mono a
inst✝ : Mono b
K : C
f g : K ⟶ pushout (fst a b) (snd a b)
w : f ≫ pushout.desc a b ⋯ = g ≫ pushout.desc a b ⋯
u : A ⟶ pushout (fst a b) (snd a b) := inl (fst a b) (snd a b)
v : B ⟶ pushout (fst a b) (snd a b) := inr (fst a b) (snd a b)
this✝ : Mono u := mono_of_isPushout_of_mono_right (of_hasPushout (fst a b) (snd a b))
this : Mono v := mono_of_isPushout_of_mono_left (of_hasPushout (fst a b) (snd a b))
sq_f_u : IsPullback (fst f u) (snd f u) f u := of_hasPullback f u
sq_f_v : IsPullback (fst f v) (snd f v) f v := of_hasPullback f v
sq_g_u : IsPullback (fst g u) (snd g u) g u := of_hasPullback g u
sq_g_v : IsPullback (fst g v) (snd g v) g v := of_hasPullback g v
l₁ : pullback f u ⟶ K := fst f u
f₁ : pullback f u ⟶ A := snd f u
l₂ : pullback f v ⟶ K := fst f v
⊢ f = g

Tactic:
let f₂ := pullback.snd f v

Goal state after:
J : Type v'
inst✝⁴ : Category.{u', v'} J
C : Type u
inst✝³ : Category.{v, u} C
W X Y Z✝ : C
f✝ : W ⟶ X
g✝ : W ⟶ Y
h : X ⟶ Z✝
i : Y ⟶ Z✝
inst✝² : Adhesive C
Z A B : C
a : A ⟶ Z
b : B ⟶ Z
inst✝¹ : Mono a
inst✝ : Mono b
K : C
f g : K ⟶ pushout (fst a b) (snd a b)
w : f ≫ pushout.desc a b ⋯ = g ≫ pushout.desc a b ⋯
u : A ⟶ pushout (fst a b) (snd a b) := inl (fst a b) (snd a b)
v : B ⟶ pushout (fst a b) (snd a b) := inr (fst a b) (snd a b)
this✝ : Mono u := mono_of_isPushout_of_mono_right (of_hasPushout (fst a b) (snd a b))
this : Mono v := mono_of_isPushout_of_mono_left (of_hasPushout (fst a b) (snd a b))
sq_f_u : IsPullback (fst f u) (snd f u) f u := of_hasPullback f u
sq_f_v : IsPullback (fst f v) (snd f v) f v := of_hasPullback f v
sq_g_u : IsPullback (fst g u) (snd g u) g u := of_hasPullback g u
sq_g_v : IsPullback (fst g v) (snd g v) g v := of_hasPullback g v
l₁ : pullback f u ⟶ K := fst f u
f₁ : pullback f u ⟶ A := snd f u
l₂ : pullback f v ⟶ K := fst f v
f₂ : pullback f v ⟶ B := snd f v
⊢ f = g
Module: Mathlib.CategoryTheory.Sites.LeftExact

Goal state before:
pp: case e_a
C : Type u
inst✝¹² : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝¹¹ : Category.{t, w} D
inst✝¹⁰ : ∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)
inst✝⁹ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
FD : D → D → Type u_1
CD : D → Type t
inst✝⁸ : (X Y : D) → FunLike (FD X Y) (CD X) (CD Y)
inst✝⁷ : ConcreteCategory D FD
inst✝⁶ : ∀ (X : C), PreservesColimitsOfShape (J.Cover X)ᵒᵖ (forget D)
inst✝⁵ : ∀ (X : C), Small.{t, max u v} (J.Cover X)ᵒᵖ
K : Type s
inst✝⁴ : SmallCategory K
inst✝³ : FinCategory K
inst✝² : HasLimitsOfShape K D
inst✝¹ : PreservesLimitsOfShape K (forget D)
inst✝ : ReflectsLimitsOfShape K (forget D)
F : K ⥤ Cᵒᵖ ⥤ D
X : C
S : Cone (F ⋙ J.plusFunctor D ⋙ (evaluation Cᵒᵖ D).obj (op X))
k : K
⊢ ((HasLimit.isoOfNatIso
            (NatIso.ofComponents (fun k ↦ colimitObjIsoColimitCompEvaluation (F ⋙ J.diagramFunctor D X).flip k)
                ⋯).symm).hom ≫
        (colimitLimitIso (F ⋙ J.diagramFunctor D X)).inv ≫
          (HasColimit.isoOfNatIso
              ((isLimitOfPreserves (J.diagramFunctor D X) (limit.isLimit F)).conePointUniqueUpToIso
                (limit.isLimit (F ⋙ J.diagramFunctor D X)))).inv) ≫
      (J.plusMap (limit.π F k)).app (op X) =
    limit.π (F ⋙ J.plusFunctor D ⋙ (evaluation Cᵒᵖ D).obj (op X)) k

Tactic:
rw [Category.assoc, Category.assoc, ← Iso.eq_inv_comp, Iso.inv_comp_eq, Iso.inv_comp_eq]

Goal state after:
case e_a
C : Type u
inst✝¹² : Category.{v, u} C
J : GrothendieckTopology C
D : Type w
inst✝¹¹ : Category.{t, w} D
inst✝¹⁰ : ∀ (P : Cᵒᵖ ⥤ D) (X : C) (S : J.Cover X), HasMultiequalizer (S.index P)
inst✝⁹ : ∀ (X : C), HasColimitsOfShape (J.Cover X)ᵒᵖ D
FD : D → D → Type u_1
CD : D → Type t
inst✝⁸ : (X Y : D) → FunLike (FD X Y) (CD X) (CD Y)
inst✝⁷ : ConcreteCategory D FD
inst✝⁶ : ∀ (X : C), PreservesColimitsOfShape (J.Cover X)ᵒᵖ (forget D)
inst✝⁵ : ∀ (X : C), Small.{t, max u v} (J.Cover X)ᵒᵖ
K : Type s
inst✝⁴ : SmallCategory K
inst✝³ : FinCategory K
inst✝² : HasLimitsOfShape K D
inst✝¹ : PreservesLimitsOfShape K (forget D)
inst✝ : ReflectsLimitsOfShape K (forget D)
F : K ⥤ Cᵒᵖ ⥤ D
X : C
S : Cone (F ⋙ J.plusFunctor D ⋙ (evaluation Cᵒᵖ D).obj (op X))
k : K
⊢ (J.plusMap (limit.π F k)).app (op X) =
    (HasColimit.isoOfNatIso
          ((isLimitOfPreserves (J.diagramFunctor D X) (limit.isLimit F)).conePointUniqueUpToIso
            (limit.isLimit (F ⋙ J.diagramFunctor D X)))).hom ≫
      (colimitLimitIso (F ⋙ J.diagramFunctor D X)).hom ≫
        (HasLimit.isoOfNatIso
              (NatIso.ofComponents (fun k ↦ colimitObjIsoColimitCompEvaluation (F ⋙ J.diagramFunctor D X).flip k)
                  ⋯).symm).inv ≫
          limit.π (F ⋙ J.plusFunctor D ⋙ (evaluation Cᵒᵖ D).obj (op X)) k
Module: Mathlib.CategoryTheory.Localization.Adjunction

Goal state before:
pp: C₁ : Type u_1
C₂ : Type u_2
D₁ : Type u_3
D₂ : Type u_4
inst✝⁶ : Category.{v_1, u_1} C₁
inst✝⁵ : Category.{v_2, u_2} C₂
inst✝⁴ : Category.{v_3, u_3} D₁
inst✝³ : Category.{v_4, u_4} D₂
G : C₁ ⥤ C₂
F : C₂ ⥤ C₁
adj : G ⊣ F
L₁ : C₁ ⥤ D₁
W₁ : MorphismProperty C₁
inst✝² : L₁.IsLocalization W₁
L₂ : C₂ ⥤ D₂
G' : D₁ ⥤ D₂
F' : D₂ ⥤ D₁
inst✝¹ : CatCommSq G L₁ L₂ G'
inst✝ : CatCommSq F L₂ L₁ F'
X₁ : C₁
this : Lifting L₁ W₁ ((G ⋙ F) ⋙ L₁) (G' ⋙ F') := { iso := (CatCommSq.iso (G ⋙ F) L₁ L₁ (G' ⋙ F')).symm }
⊢ (ε adj L₁ W₁ L₂ G' F').app (L₁.obj X₁) =
    L₁.map (adj.unit.app X₁) ≫
      (CatCommSq.iso F L₂ L₁ F').hom.app (G.obj X₁) ≫ F'.map ((CatCommSq.iso G L₁ L₂ G').hom.app X₁)

Tactic:
simp only [ε, liftNatTrans_app, Lifting.iso, Iso.symm,
    Functor.id_obj, Functor.comp_obj, Functor.rightUnitor_hom_app,
      whiskerRight_app, CatCommSq.hComp_iso_hom_app, id_comp]

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

Goal state before:
pp: case mp
C : Type u
inst✝ : Category.{v, u} C
X Y : C
c : BinaryCofan X Y
⊢ IsVanKampenColimit c →
    ∀ {X' Y' : C} (c' : BinaryCofan X' Y') (αX : X' ⟶ X) (αY : Y' ⟶ Y) (f : c'.pt ⟶ c.pt),
      αX ≫ c.inl = c'.inl ≫ f →
        αY ≫ c.inr = c'.inr ≫ f →
          (Nonempty (IsColimit c') ↔ IsPullback c'.inl αX f c.inl ∧ IsPullback c'.inr αY f c.inr)

Tactic:
introv H hαX hαY
    rw [H c' (mapPair αX αY) f (by ext ⟨⟨⟩⟩ <;> dsimp <;> assumption) (.of_discrete _)]
    constructor
    · intro H
      exact ⟨H _, H _⟩
    · rintro H ⟨⟨⟩⟩
      exacts [H.1, H.2]

Goal state after:
Module: Mathlib.CategoryTheory.Localization.Bousfield

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝¹ : Category.{v_1, u_1} C
inst✝ : Category.{v_2, u_2} D
P : ObjectProperty C
X✝ Y✝ Z✝ : C
f : X✝ ⟶ Y✝
g : Y✝ ⟶ Z✝
hf : P.isLocal f
hfg : P.isLocal (f ≫ g)
Z : C
hZ : P Z
⊢ Function.Bijective fun g_1 ↦ g ≫ g_1

Tactic:
rw [← Function.Bijective.of_comp_iff' (hf Z hZ)]

Goal state after:
C : Type u_1
D : Type u_2
inst✝¹ : Category.{v_1, u_1} C
inst✝ : Category.{v_2, u_2} D
P : ObjectProperty C
X✝ Y✝ Z✝ : C
f : X✝ ⟶ Y✝
g : Y✝ ⟶ Z✝
hf : P.isLocal f
hfg : P.isLocal (f ≫ g)
Z : C
hZ : P Z
⊢ Function.Bijective ((fun g ↦ f ≫ g) ∘ fun g_1 ↦ g ≫ g_1)
Module: Mathlib.CategoryTheory.Limits.VanKampen

Goal state before:
pp: case mpr
C : Type u
inst✝ : Category.{v, u} C
X Y : C
c : BinaryCofan X Y
cofans : (X Y : C) → BinaryCofan X Y
colimits : (X Y : C) → IsColimit (cofans X Y)
cones : {X Y Z : C} → (f : X ⟶ Z) → (g : Y ⟶ Z) → PullbackCone f g
limits : {X Y Z : C} → (f : X ⟶ Z) → (g : Y ⟶ Z) → IsLimit (cones f g)
h₁ :
  ∀ {X' Y' : C} (αX : X' ⟶ X) (αY : Y' ⟶ Y) (f : (cofans X' Y').pt ⟶ c.pt),
    αX ≫ c.inl = (cofans X' Y').inl ≫ f →
      αY ≫ c.inr = (cofans X' Y').inr ≫ f →
        IsPullback (cofans X' Y').inl αX f c.inl ∧ IsPullback (cofans X' Y').inr αY f c.inr
h₂ : {Z : C} → (f : Z ⟶ c.pt) → IsColimit (BinaryCofan.mk (cones f c.inl).fst (cones f c.inr).fst)
X' Y' : C
c' : BinaryCofan X' Y'
αX : X' ⟶ X
αY : Y' ⟶ Y
f : c'.pt ⟶ c.pt
hX : αX ≫ c.inl = c'.inl ≫ f
hY : αY ≫ c.inr = c'.inr ≫ f
H₁ : IsPullback c'.inl αX f c.inl
H₂ : IsPullback c'.inr αY f c.inr
⊢ Nonempty (IsColimit c')

Tactic:
refine ⟨IsColimit.ofIsoColimit ?_ <| (isoBinaryCofanMk _).symm⟩

Goal state after:
case mpr
C : Type u
inst✝ : Category.{v, u} C
X Y : C
c : BinaryCofan X Y
cofans : (X Y : C) → BinaryCofan X Y
colimits : (X Y : C) → IsColimit (cofans X Y)
cones : {X Y Z : C} → (f : X ⟶ Z) → (g : Y ⟶ Z) → PullbackCone f g
limits : {X Y Z : C} → (f : X ⟶ Z) → (g : Y ⟶ Z) → IsLimit (cones f g)
h₁ :
  ∀ {X' Y' : C} (αX : X' ⟶ X) (αY : Y' ⟶ Y) (f : (cofans X' Y').pt ⟶ c.pt),
    αX ≫ c.inl = (cofans X' Y').inl ≫ f →
      αY ≫ c.inr = (cofans X' Y').inr ≫ f →
        IsPullback (cofans X' Y').inl αX f c.inl ∧ IsPullback (cofans X' Y').inr αY f c.inr
h₂ : {Z : C} → (f : Z ⟶ c.pt) → IsColimit (BinaryCofan.mk (cones f c.inl).fst (cones f c.inr).fst)
X' Y' : C
c' : BinaryCofan X' Y'
αX : X' ⟶ X
αY : Y' ⟶ Y
f : c'.pt ⟶ c.pt
hX : αX ≫ c.inl = c'.inl ≫ f
hY : αY ≫ c.inr = c'.inr ≫ f
H₁ : IsPullback c'.inl αX f c.inl
H₂ : IsPullback c'.inr αY f c.inr
⊢ IsColimit (BinaryCofan.mk c'.inl c'.inr)
Module: Mathlib.CategoryTheory.Sites.PreservesSheafification

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
J : GrothendieckTopology C
A : Type u_1
B : Type u_2
inst✝² : Category.{v_1, u_1} A
inst✝¹ : Category.{v_2, u_2} B
F : A ⥤ B
G₁ : (Cᵒᵖ ⥤ A) ⥤ Sheaf J A
adj₁ : G₁ ⊣ sheafToPresheaf J A
G₂ : (Cᵒᵖ ⥤ B) ⥤ Sheaf J B
adj₂ : G₂ ⊣ sheafToPresheaf J B
inst✝ : J.HasSheafCompose F
P : Cᵒᵖ ⥤ A
⊢ J.W (adj₂.unit.app (P ⋙ F) ≫ (sheafToPresheaf J B).map ((sheafComposeNatTrans J F adj₁ adj₂).app P)) ↔
    J.W ((sheafToPresheaf J B).map ((sheafComposeNatTrans J F adj₁ adj₂).app P))

Tactic:
(W _).precomp_iff _ _ (J.W_adj_unit_app adj₂ (P ⋙ F))

Goal state after:
C : Type u
inst✝³ : Category.{v, u} C
J : GrothendieckTopology C
A : Type u_1
B : Type u_2
inst✝² : Category.{v_1, u_1} A
inst✝¹ : Category.{v_2, u_2} B
F : A ⥤ B
G₁ : (Cᵒᵖ ⥤ A) ⥤ Sheaf J A
adj₁ : G₁ ⊣ sheafToPresheaf J A
G₂ : (Cᵒᵖ ⥤ B) ⥤ Sheaf J B
adj₂ : G₂ ⊣ sheafToPresheaf J B
inst✝ : J.HasSheafCompose F
P : Cᵒᵖ ⥤ A
⊢ J.W ((sheafToPresheaf J B).map ((sheafComposeNatTrans J F adj₁ adj₂).app P)) ↔
    J.W ((sheafToPresheaf J B).map ((sheafComposeNatTrans J F adj₁ adj₂).app P))
Module: Mathlib.CategoryTheory.Sites.LocallySurjective

Goal state before:
pp: case mpr
C : Type u
inst✝¹ : Category.{v, u} C
J : GrothendieckTopology C
F G : Sheaf J (Type w)
φ : F ⟶ G
inst✝ : HasSheafify J (Type w)
a✝ : Epi φ
this : Epi (imageι φ)
⊢ IsIso (imageι φ)

Tactic:
apply isIso_of_mono_of_epi

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

Goal state before:
pp: case succ
C : Type u
inst✝² : Category.{v, u} C
inst✝¹ : Abelian C
X : C
n : ℕ
inst✝ : Projective X
this : HasExt C := HasExt.standard C
Y : C
i : ℕ
hi : 1 ≤ i + 1
e : Ext X Y (i + 1)
⊢ e = 0

Tactic:
exact e.eq_zero_of_projective

Goal state after:
Module: Mathlib.Algebra.Category.ModuleCat.Sheaf.Free

Goal state before:
pp: C : Type u₁
inst✝² : Category.{v₁, u₁} C
J✝ : GrothendieckTopology C
R : Sheaf J✝ RingCat
inst✝¹ : HasWeakSheafify J✝ AddCommGrpCat
inst✝ : J✝.WEqualsLocallyBijective AddCommGrpCat
I J : Type u
⊢ coprod.inr ≫ (freeSumIso I J).hom = freeFunctor.map (↾Sum.inr)

Tactic:
exact IsColimit.comp_coconePointUniqueUpToIso_hom
    (coprodIsCoprod (free (R := R) I) (free J)) _ (.mk .right)

Goal state after:
Module: Mathlib.CategoryTheory.Functor.Flat

Goal state before:
pp: C : Type u₁
inst✝⁴ : Category.{v₁, u₁} C
D : Type u₂
inst✝³ : Category.{v₂, u₂} D
J : Type v₁
inst✝² : SmallCategory J
inst✝¹ : FinCategory J
F : C ⥤ D
inst✝ : RepresentablyFlat F
K : J ⥤ C
c : Cone K
hc : IsLimit c
s : Cone (K ⋙ F)
f₁ f₂ : s.pt ⟶ F.obj c.pt
h₁ : ∀ (j : J), f₁ ≫ (F.mapCone c).π.app j = s.π.app j
h₂ : ∀ (j : J), f₂ ≫ (F.mapCone c).π.app j = s.π.app j
X : J
⊢ ((F.mapCone c).toStructuredArrow ⋙ map f₁).obj X = s.toStructuredArrow.obj X

Tactic:
simp [← h₁]

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

Goal state before:
pp: case a
C : Type u
inst✝ : Category.{v, u} C
S : C
E : PreZeroHypercover S
F : PreZeroHypercover S
⊢ Presieve.ofArrows E.X E.f ⊔ Presieve.ofArrows F.X F.f ≤ Presieve.ofArrows (E.sum F).X (E.sum F).f

Tactic:
· rintro Z g (⟨⟨i⟩⟩ | ⟨⟨i⟩⟩)
    · exact ⟨Sum.inl i⟩
    · exact ⟨Sum.inr i⟩

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

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
A : Type u_1
inst✝ : Category.{v_1, u_1} A
S : C
E : PreOneHypercover S
c : Cofan E.X
hc : IsColimit c
d : Cofan E.Y'
hd : IsColimit d
F : Cᵒᵖ ⥤ A
⊢ F.map (Cofan.IsColimit.desc hc E.f).op ≫ F.map (Cofan.IsColimit.desc hd fun x ↦ E.p₁ x.snd ≫ c.inj x.fst.1).op =
    F.map (Cofan.IsColimit.desc hc E.f).op ≫ F.map (Cofan.IsColimit.desc hd fun x ↦ E.p₂ x.snd ≫ c.inj x.fst.2).op

Tactic:
by
    simp_rw [← Functor.map_comp, ← op_comp]
    congr 2
    exact Cofan.IsColimit.hom_ext hd _ _ (by simp [E.w])

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

Goal state before:
pp: case left
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Category.{v_2, u_2} D
G : C ⥤ D
J : GrothendieckTopology C
K : GrothendieckTopology D
A : Type w
inst✝² : Category.{w', w} A
inst✝¹ : ∀ (X : Dᵒᵖ), Limits.HasLimitsOfShape (StructuredArrow X G.op) A
inst✝ : IsDenseSubsite J K G
Y : Sheaf J A
U : C
X : A
f₁ f₂ : (yoneda.obj (((G.op.ran ⋙ (whiskeringLeft Cᵒᵖ Dᵒᵖ A).obj G.op).obj Y.obj).obj (op U))).obj (op X)
e :
  (ConcreteCategory.hom ((yoneda.map ((G.op.ranCounit.app Y.obj).app (op U))).app (op X))) f₁ =
    (ConcreteCategory.hom ((yoneda.map ((G.op.ranCounit.app Y.obj).app (op U))).app (op X))) f₂
g : StructuredArrow (op (G.obj U)) G.op
⊢ f₁ ≫ ((RightExtension.mk (G.op.ran.obj Y.obj) (G.op.ranCounit.app Y.obj)).coneAt (op (G.obj U))).π.app g =
    f₂ ≫ ((RightExtension.mk (G.op.ran.obj Y.obj) (G.op.ranCounit.app Y.obj)).coneAt (op (G.obj U))).π.app g

Tactic:
obtain ⟨⟨W⟩, ⟨g : G.obj W ⟶ G.obj U⟩, rfl⟩ := g.mk_surjective

Goal state after:
case left
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Category.{v_2, u_2} D
G : C ⥤ D
J : GrothendieckTopology C
K : GrothendieckTopology D
A : Type w
inst✝² : Category.{w', w} A
inst✝¹ : ∀ (X : Dᵒᵖ), Limits.HasLimitsOfShape (StructuredArrow X G.op) A
inst✝ : IsDenseSubsite J K G
Y : Sheaf J A
U : C
X : A
f₁ f₂ : (yoneda.obj (((G.op.ran ⋙ (whiskeringLeft Cᵒᵖ Dᵒᵖ A).obj G.op).obj Y.obj).obj (op U))).obj (op X)
e :
  (ConcreteCategory.hom ((yoneda.map ((G.op.ranCounit.app Y.obj).app (op U))).app (op X))) f₁ =
    (ConcreteCategory.hom ((yoneda.map ((G.op.ranCounit.app Y.obj).app (op U))).app (op X))) f₂
W : C
g : G.obj W ⟶ G.obj U
⊢ f₁ ≫
      ((RightExtension.mk (G.op.ran.obj Y.obj) (G.op.ranCounit.app Y.obj)).coneAt (op (G.obj U))).π.app
        (StructuredArrow.mk (op g)) =
    f₂ ≫
      ((RightExtension.mk (G.op.ran.obj Y.obj) (G.op.ranCounit.app Y.obj)).coneAt (op (G.obj U))).π.app
        (StructuredArrow.mk (op g))
Module: Mathlib.CategoryTheory.Sites.Hypercover.One

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
J : GrothendieckTopology C
X : C
S : J.Cover X
f₁ f₂ : S.Arrow
W : C
p₁ : W ⟶ f₁.Y
p₂ : W ⟶ f₂.Y
w : p₁ ≫ f₁.f = p₂ ≫ f₂.f
⊢ S.preOneHypercover.sieve₁ p₁ p₂ = ⊤

Tactic:
by
  ext Y f
  simp only [Sieve.top_apply, iff_true]
  exact ⟨{ w := w, .. }, f, rfl, rfl⟩

Goal state after:
Module: Mathlib.Topology.Sheaves.Presheaf

Goal state before:
pp: X : TopCat
C : Type u
inst✝² : Category.{v, u} C
FC : C → C → Type u_1
CC : C → Type u_2
inst✝¹ : (X Y : C) → FunLike (FC X Y) (CC X) (CC Y)
inst✝ : ConcreteCategory C FC
F : Presheaf C X
U V W : Opens ↑X
e₁ : U ≤ V
e₂ : V ≤ W
x : ToType (F.obj (op W))
⊢ (ConcreteCategory.hom (F.map (homOfLE e₁).op)) ((ConcreteCategory.hom (F.map (homOfLE e₂).op)) x) =
    (ConcreteCategory.hom (F.map (homOfLE ⋯).op)) x

Tactic:
rw [← ConcreteCategory.comp_apply, ← Functor.map_comp]

Goal state after:
X : TopCat
C : Type u
inst✝² : Category.{v, u} C
FC : C → C → Type u_1
CC : C → Type u_2
inst✝¹ : (X Y : C) → FunLike (FC X Y) (CC X) (CC Y)
inst✝ : ConcreteCategory C FC
F : Presheaf C X
U V W : Opens ↑X
e₁ : U ≤ V
e₂ : V ≤ W
x : ToType (F.obj (op W))
⊢ (ConcreteCategory.hom (F.map ((homOfLE e₂).op ≫ (homOfLE e₁).op))) x = (ConcreteCategory.hom (F.map (homOfLE ⋯).op)) x