Theorem: ArzelaAscoli.isCompact_closure_of_closedEmbedding
File: Mathlib/Topology/UniformSpace/Ascoli.lean

Proof steps:
state_before: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
⊢ IsCompact (closure s)
state_after: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
⊢ CompactSpace ↑(closure s)
tactic: rw [isCompact_iff_compactSpace]
state_before: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
⊢ CompactSpace ↑(closure s)
state_after: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
this : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F)
⊢ CompactSpace ↑(closure s)
tactic: have : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F) := fun K hK x hx ↦
    UniformOnFun.uniformContinuous_eval_of_mem _ _ hx hK |>.continuous.comp F_clemb.continuous
state_before: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
this : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F)
⊢ CompactSpace ↑(closure s)
state_after: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
this : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F)
cls_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
⊢ CompactSpace ↑(closure s)
tactic: have cls_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ ((↑) : closure s → ι)) K :=
    fun K hK ↦ (s_eqcont K hK).closure' <| show Continuous (K.restrict ∘ F) from
      continuous_pi fun ⟨x, hx⟩ ↦ this K hK x hx
state_before: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
this : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F)
cls_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
⊢ CompactSpace ↑(closure s)
state_after: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
this : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F)
cls_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
cls_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ closure s, F i x ∈ Q
⊢ CompactSpace ↑(closure s)
tactic: have cls_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ closure s, F i x ∈ Q :=
    fun K hK x hx ↦ (s_pointwiseCompact K hK x hx).imp fun Q hQ ↦ ⟨hQ.1, closure_minimal hQ.2 <|
      hQ.1.isClosed.preimage (this K hK x hx)⟩
state_before: ι : Type u_1
X : Type u_2
Y : Type u_3
α : Type u_4
β : Type u_5
inst✝⁴ : TopologicalSpace X
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
F : ι → X → α
G : ι → β → α
inst✝¹ : TopologicalSpace ι
inst✝ : T2Space α
𝔖 : Set (Set X)
𝔖_compact : ∀ K ∈ 𝔖, IsCompact K
F_clemb : ClosedEmbedding (⇑(UniformOnFun.ofFun 𝔖) ∘ F)
s : Set ι
s_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
s_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ s, F i x ∈ Q
this : ∀ K ∈ 𝔖, ∀ x ∈ K, Continuous (eval x ∘ F)
cls_eqcont : ∀ K ∈ 𝔖, EquicontinuousOn (F ∘ Subtype.val) K
cls_pointwiseCompact : ∀ K ∈ 𝔖, ∀ x ∈ K, ∃ Q, IsCompact Q ∧ ∀ i ∈ closure s, F i x ∈ Q
⊢ CompactSpace ↑(closure s)
state_after: no goals
tactic: exact ArzelaAscoli.compactSpace_of_closedEmbedding 𝔖_compact
    (F_clemb.comp isClosed_closure.closedEmbedding_subtype_val) cls_eqcont
    fun K hK x hx ↦ (cls_pointwiseCompact K hK x hx).imp fun Q hQ ↦ ⟨hQ.1, by simpa using hQ.2⟩