Theorem: CategoryTheory.Comonad.ForgetCreatesLimits'.liftedConeIsLimit_lift_f
File: Mathlib/CategoryTheory/Monad/Limits.lean

Proof steps:
state_before: C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J : Type u
inst✝³ : Category.{v, u} J
T : Comonad C
D : J ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
j : J
⊢ (s.pt.a ≫ T.map (t.lift (T.forget.mapCone s))) ≫ (T.mapCone c).π.app j =
    (t.lift (T.forget.mapCone s) ≫ (liftedCone c t).pt.a) ≫ (T.mapCone c).π.app j
state_after: C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J : Type u
inst✝³ : Category.{v, u} J
T : Comonad C
D : J ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
j : J
⊢ (s.pt.a ≫ T.map (t.lift (T.forget.mapCone s))) ≫ T.map (c.π.app j) =
    (t.lift (T.forget.mapCone s) ≫ lambda c t) ≫ T.map (c.π.app j)
tactic: dsimp
state_before: C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J : Type u
inst✝³ : Category.{v, u} J
T : Comonad C
D : J ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
j : J
⊢ (s.pt.a ≫ T.map (t.lift (T.forget.mapCone s))) ≫ T.map (c.π.app j) =
    (t.lift (T.forget.mapCone s) ≫ lambda c t) ≫ T.map (c.π.app j)
state_after: C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J : Type u
inst✝³ : Category.{v, u} J
T : Comonad C
D : J ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
j : J
⊢ s.pt.a ≫ T.map ((T.forget.mapCone s).π.app j) = (T.forget.mapCone s).π.app j ≫ (D.obj j).a
tactic: rw [Category.assoc, ← t.fac, Category.assoc, t.fac, commuting, ← assoc, ← assoc, t.fac,
            assoc, ← Functor.map_comp, t.fac]
state_before: C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J : Type u
inst✝³ : Category.{v, u} J
T : Comonad C
D : J ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
j : J
⊢ s.pt.a ≫ T.map ((T.forget.mapCone s).π.app j) = (T.forget.mapCone s).π.app j ≫ (D.obj j).a
state_after: no goals
tactic: exact (s.π.app j).h
state_before: C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
⊢ m = (fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s
state_after: case h
C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
⊢ m.f = ((fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s).f
tactic: ext1
state_before: case h
C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
⊢ m.f = ((fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s).f
state_after: case h
C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
⊢ ∀ (j : J✝), m.f ≫ c.π.app j = ((fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s).f ≫ c.π.app j
tactic: apply t.hom_ext
state_before: case h
C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
⊢ ∀ (j : J✝), m.f ≫ c.π.app j = ((fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s).f ≫ c.π.app j
state_after: case h
C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
j : J✝
⊢ m.f ≫ c.π.app j = ((fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s).f ≫ c.π.app j
tactic: intro j
state_before: case h
C : Type u₁
inst✝⁵ : Category.{v₁, u₁} C
D✝ : Type u₂
inst✝⁴ : Category.{v₂, u₂} D✝
J✝ : Type u
inst✝³ : Category.{v, u} J✝
T : Comonad C
D : J✝ ⥤ T.Coalgebra
c : Cone (D ⋙ T.forget)
t : IsLimit c
inst✝² : PreservesLimit (D ⋙ T.forget) T.toFunctor
inst✝¹ : PreservesLimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
inst✝ : PreservesColimit ((D ⋙ T.forget) ⋙ T.toFunctor) T.toFunctor
s : Cone D
m : s.pt ⟶ (liftedCone c t).pt
J : ∀ (j : J✝), m ≫ (liftedCone c t).π.app j = s.π.app j
j : J✝
⊢ m.f ≫ c.π.app j = ((fun s => { f := t.lift (T.forget.mapCone s), h := ⋯ }) s).f ≫ c.π.app j
state_after: no goals
tactic: simpa using congr_arg Coalgebra.Hom.f (J j)