-- Mathlib/Topology/Algebra/Equicontinuity.lean
theorem equicontinuous_of_equicontinuousAt_one {ι G M hom : Type*} [TopologicalSpace G]
    [UniformSpace M] [Group G] [Group M] [IsTopologicalGroup G] [UniformGroup M]
    [FunLike hom G M] [MonoidHomClass hom G M] (F : ι → hom)
    (hf : EquicontinuousAt ((↑) ∘ F) (1 : G)) :
    Equicontinuous ((↑) ∘ F)

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
φ : G →* ι →ᵤ M := { toFun := swap (DFunLike.coe ∘ F), map_one' := ⋯, map_mul' := ⋯ }
⊢ Continuous (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F))

Tactic:
exact continuous_of_continuousAt_one φ hf

Result:
no goals

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
a b : G
⊢ swap (DFunLike.coe ∘ F) (a * b) = swap (DFunLike.coe ∘ F) a * swap (DFunLike.coe ∘ F) b

Tactic:
ext

Result:
case h
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
a b : G
x✝ : ι
⊢ swap (DFunLike.coe ∘ F) (a * b) x✝ = (swap (DFunLike.coe ∘ F) a * swap (DFunLike.coe ∘ F) b) x✝

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
⊢ swap (DFunLike.coe ∘ F) 1 = 1

Tactic:
ext

Result:
case h
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
x✝ : ι
⊢ swap (DFunLike.coe ∘ F) 1 x✝ = 1 x✝

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
⊢ Continuous (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F))

Tactic:
let φ : G →* (ι →ᵤ M) :=
  { toFun := swap ((↑) ∘ F)
    map_one' := by dsimp [UniformFun]; ext; exact map_one _
    map_mul' := fun a b => by dsimp [UniformFun]; ext; exact map_mul _ _ _ }

Result:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
φ : G →* ι →ᵤ M := { toFun := swap (DFunLike.coe ∘ F), map_one' := ⋯, map_mul' := ⋯ }
⊢ Continuous (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F))

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : EquicontinuousAt (DFunLike.coe ∘ F) 1
⊢ Equicontinuous (DFunLike.coe ∘ F)

Tactic:
rw [equicontinuous_iff_continuous]

Result:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : EquicontinuousAt (DFunLike.coe ∘ F) 1
⊢ Continuous (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F))

Proof state:
case h
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
x✝ : ι
⊢ swap (DFunLike.coe ∘ F) 1 x✝ = 1 x✝

Tactic:
exact map_one _

Result:
no goals

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : EquicontinuousAt (DFunLike.coe ∘ F) 1
⊢ Continuous (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F))

Tactic:
rw [equicontinuousAt_iff_continuousAt] at hf

Result:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
⊢ Continuous (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F))

Proof state:
case h
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
a b : G
x✝ : ι
⊢ swap (DFunLike.coe ∘ F) (a * b) x✝ = (swap (DFunLike.coe ∘ F) a * swap (DFunLike.coe ∘ F) b) x✝

Tactic:
exact map_mul _ _ _

Result:
no goals

Proof state:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
a b : G
⊢ { toFun := swap (DFunLike.coe ∘ F), map_one' := ⋯ }.toFun (a * b) =
    { toFun := swap (DFunLike.coe ∘ F), map_one' := ⋯ }.toFun a *
      { toFun := swap (DFunLike.coe ∘ F), map_one' := ⋯ }.toFun b

Tactic:
dsimp [UniformFun]

Result:
ι : Type u_1
G : Type u_2
M : Type u_3
hom : Type u_4
inst✝⁷ : TopologicalSpace G
inst✝⁶ : UniformSpace M
inst✝⁵ : Group G
inst✝⁴ : Group M
inst✝³ : IsTopologicalGroup G
inst✝² : UniformGroup M
inst✝¹ : FunLike hom G M
inst✝ : MonoidHomClass hom G M
F : ι → hom
hf : ContinuousAt (⇑UniformFun.ofFun ∘ swap (DFunLike.coe ∘ F)) 1
a b : G
⊢ swap (DFunLike.coe ∘ F) (a * b) = swap (DFunLike.coe ∘ F) a * swap (DFunLike.coe ∘ F) b