Theorem: uniform_extend_subtype
File: Mathlib/Topology/UniformSpace/UniformEmbedding.lean

tactic: have de : DenseEmbedding e := he.denseEmbedding hd
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: have de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e) := de.subtype p
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: have ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e) := uniformEmbedding_subtypeEmb _ he de
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: have : b ∈ closure (e '' { x | p x }) :=
  (closure_mono <| monotone_image <| hp) (mem_of_mem_nhds hb)
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: let ⟨c, hc⟩ := uniformly_extend_exists ue'.toUniformInducing de'.dense hf ⟨b, this⟩
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: replace hc : Tendsto (f ∘ Subtype.val) (((𝓝 b).comap e).comap Subtype.val) (𝓝 c) := by
  simpa only [nhds_subtype_eq_comap, comap_comap, DenseEmbedding.subtypeEmb_coe] using hc
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
c : γ
hc : Tendsto (fun x => f ↑x) (comap (DenseEmbedding.subtypeEmb p e) (𝓝 { val := b, property := this })) (𝓝 c)
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: refine ⟨c, (tendsto_comap'_iff ?_).1 hc⟩
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
c : γ
hc : Tendsto (f ∘ Subtype.val) (comap Subtype.val (comap e (𝓝 b))) (𝓝 c)
⊢ ∃ c, Tendsto f (comap e (𝓝 b)) (𝓝 c)

tactic: rw [Subtype.range_coe_subtype]
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
c : γ
hc : Tendsto (f ∘ Subtype.val) (comap Subtype.val (comap e (𝓝 b))) (𝓝 c)
⊢ range Subtype.val ∈ comap e (𝓝 b)

tactic: exact ⟨_, hb, by rwa [← de.toInducing.closure_eq_preimage_closure_image, hs.closure_eq]⟩
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
c : γ
hc : Tendsto (f ∘ Subtype.val) (comap Subtype.val (comap e (𝓝 b))) (𝓝 c)
⊢ {x | p x} ∈ comap e (𝓝 b)

tactic: simpa only [nhds_subtype_eq_comap, comap_comap, DenseEmbedding.subtypeEmb_coe] using hc
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
c : γ
hc : Tendsto (fun x => f ↑x) (comap (DenseEmbedding.subtypeEmb p e) (𝓝 { val := b, property := this })) (𝓝 c)
⊢ Tendsto (f ∘ Subtype.val) (comap Subtype.val (comap e (𝓝 b))) (𝓝 c)

tactic: rwa [← de.toInducing.closure_eq_preimage_closure_image, hs.closure_eq]
state_before: α : Type u_2
β : Type u_3
γ : Type u_1
inst✝³ : UniformSpace α
inst✝² : UniformSpace β
inst✝¹ : UniformSpace γ
e✝ : β → α
h_e : UniformInducing e✝
h_dense : DenseRange e✝
f✝ : β → γ
h_f : UniformContinuous f✝
inst✝ : CompleteSpace γ
p : α → Prop
e : α → β
f : α → γ
b : β
s : Set α
hf : UniformContinuous fun x => f ↑x
he : UniformEmbedding e
hd : ∀ (x : β), x ∈ closure (range e)
hb : closure (e '' s) ∈ 𝓝 b
hs : IsClosed s
hp : ∀ (x : α), x ∈ s → p x
de : DenseEmbedding e
de' : DenseEmbedding (DenseEmbedding.subtypeEmb p e)
ue' : UniformEmbedding (DenseEmbedding.subtypeEmb p e)
this : b ∈ closure (e '' {x | p x})
c : γ
hc : Tendsto (f ∘ Subtype.val) (comap Subtype.val (comap e (𝓝 b))) (𝓝 c)
⊢ e ⁻¹' closure (e '' s) ⊆ {x | p x}