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coe_top [CompactSpace α] [Nonempty α] : (↑(⊤ : PositiveCompacts α) : Set α) = univ := rfl
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_top
null
protected map (f : α → β) (hf : Continuous f) (hf' : IsOpenMap f) (K : PositiveCompacts α) : PositiveCompacts β := { Compacts.map f hf K.toCompacts with interior_nonempty' := (K.interior_nonempty'.image _).mono (hf'.image_interior_subset K.toCompacts) } @[simp, norm_cast]
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
map
The image of a positive compact set under a continuous open map.
coe_map {f : α → β} (hf : Continuous f) (hf' : IsOpenMap f) (s : PositiveCompacts α) : (s.map f hf hf' : Set β) = f '' s := rfl @[simp]
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_map
null
map_id (K : PositiveCompacts α) : K.map id continuous_id IsOpenMap.id = K := PositiveCompacts.ext <| Set.image_id _
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
map_id
null
map_comp (f : β → γ) (g : α → β) (hf : Continuous f) (hg : Continuous g) (hf' : IsOpenMap f) (hg' : IsOpenMap g) (K : PositiveCompacts α) : K.map (f ∘ g) (hf.comp hg) (hf'.comp hg') = (K.map g hg hg').map f hf hf' := PositiveCompacts.ext <| Set.image_comp _ _ _
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
map_comp
null
_root_.exists_positiveCompacts_subset [LocallyCompactSpace α] {U : Set α} (ho : IsOpen U) (hn : U.Nonempty) : ∃ K : PositiveCompacts α, ↑K ⊆ U := let ⟨x, hx⟩ := hn let ⟨K, hKc, hxK, hKU⟩ := exists_compact_subset ho hx ⟨⟨⟨K, hKc⟩, ⟨x, hxK⟩⟩, hKU⟩
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
_root_.exists_positiveCompacts_subset
null
_root_.IsOpen.exists_positiveCompacts_closure_subset [R1Space α] [LocallyCompactSpace α] {U : Set α} (ho : IsOpen U) (hn : U.Nonempty) : ∃ K : PositiveCompacts α, closure ↑K ⊆ U := let ⟨K, hKU⟩ := exists_positiveCompacts_subset ho hn ⟨K, K.isCompact.closure_subset_of_isOpen ho hKU⟩
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
_root_.IsOpen.exists_positiveCompacts_closure_subset
null
nonempty' [WeaklyLocallyCompactSpace α] [Nonempty α] : Nonempty (PositiveCompacts α) := by inhabit α rcases exists_compact_mem_nhds (default : α) with ⟨K, hKc, hK⟩ exact ⟨⟨K, hKc⟩, _, mem_interior_iff_mem_nhds.2 hK⟩
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
nonempty'
In a nonempty locally compact space, there exists a compact set with nonempty interior.
protected prod (K : PositiveCompacts α) (L : PositiveCompacts β) : PositiveCompacts (α × β) where toCompacts := K.toCompacts.prod L.toCompacts interior_nonempty' := by simp only [Compacts.carrier_eq_coe, Compacts.coe_prod, interior_prod_eq] exact K.interior_nonempty.prod L.interior_nonempty @[simp]
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
prod
The product of two `TopologicalSpace.PositiveCompacts`, as a `TopologicalSpace.PositiveCompacts` in the product space.
coe_prod (K : PositiveCompacts α) (L : PositiveCompacts β) : (K.prod L : Set (α × β)) = (K : Set α) ×ˢ (L : Set β) := rfl
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_prod
null
CompactOpens (α : Type*) [TopologicalSpace α] extends Compacts α where isOpen' : IsOpen carrier
structure
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
CompactOpens
The type of compact open sets of a topological space. This is useful in non-Hausdorff contexts, in particular spectral spaces.
Simps.coe (s : CompactOpens α) : Set α := s initialize_simps_projections CompactOpens (carrier → coe, as_prefix coe)
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
Simps.coe
See Note [custom simps projection].
protected isCompact (s : CompactOpens α) : IsCompact (s : Set α) := s.isCompact'
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
isCompact
null
protected isOpen (s : CompactOpens α) : IsOpen (s : Set α) := s.isOpen'
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
isOpen
null
@[simps] toOpens (s : CompactOpens α) : Opens α := ⟨s, s.isOpen⟩
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
toOpens
Reinterpret a compact open as an open.
@[simps] toClopens [T2Space α] (s : CompactOpens α) : Clopens α := ⟨s, s.isCompact.isClosed, s.isOpen⟩ @[ext]
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
toClopens
Reinterpret a compact open as a clopen.
protected ext {s t : CompactOpens α} (h : (s : Set α) = t) : s = t := SetLike.ext' h @[simp]
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
ext
null
coe_mk (s : Compacts α) (h) : (mk s h : Set α) = s := rfl
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_mk
null
@[simp, norm_cast] coe_sup (s t : CompactOpens α) : ↑(s ⊔ t) = (s ∪ t : Set α) := rfl @[simp, norm_cast] lemma coe_bot : ↑(⊥ : CompactOpens α) = (∅ : Set α) := rfl
lemma
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_sup
null
@[simp] coe_finsetSup {ι : Type*} {f : ι → CompactOpens α} {s : Finset ι} : (↑(s.sup f) : Set α) = ⋃ i ∈ s, f i := by classical induction s using Finset.induction_on <;> simp [*]
lemma
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_finsetSup
null
instInf : Min (CompactOpens α) where min U V := ⟨⟨U ∩ V, QuasiSeparatedSpace.inter_isCompact U.1.1 V.1.1 U.2 U.1.2 V.2 V.1.2⟩, U.2.inter V.2⟩ @[simp, norm_cast] lemma coe_inf (s t : CompactOpens α) : ↑(s ⊓ t) = (s ∩ t : Set α) := rfl
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instInf
null
instSemilatticeInf : SemilatticeInf (CompactOpens α) := SetLike.coe_injective.semilatticeInf _ coe_inf
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instSemilatticeInf
null
instSDiff : SDiff (CompactOpens α) where sdiff s t := ⟨⟨s \ t, s.isCompact.diff t.isOpen⟩, s.isOpen.sdiff t.isCompact.isClosed⟩ @[simp, norm_cast] lemma coe_sdiff (s t : CompactOpens α) : ↑(s \ t) = (s \ t : Set α) := rfl
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instSDiff
null
instGeneralizedBooleanAlgebra : GeneralizedBooleanAlgebra (CompactOpens α) := SetLike.coe_injective.generalizedBooleanAlgebra _ coe_sup coe_inf coe_bot coe_sdiff
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instGeneralizedBooleanAlgebra
null
instTop : Top (CompactOpens α) where top := ⟨⊤, isOpen_univ⟩ @[simp, norm_cast] lemma coe_top : ↑(⊤ : CompactOpens α) = (univ : Set α) := rfl
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instTop
null
instBoundedOrder : BoundedOrder (CompactOpens α) := BoundedOrder.lift ((↑) : _ → Set α) (fun _ _ => id) coe_top coe_bot
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instBoundedOrder
null
instHasCompl : HasCompl (CompactOpens α) where compl s := ⟨⟨sᶜ, s.isOpen.isClosed_compl.isCompact⟩, s.isCompact.isClosed.isOpen_compl⟩
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instHasCompl
null
instHImp : HImp (CompactOpens α) where himp s t := ⟨⟨s ⇨ t, IsClosed.isCompact (by simpa [himp_eq] using t.isCompact.isClosed.union s.isOpen.isClosed_compl)⟩, by simpa [himp_eq] using t.isOpen.union s.isCompact.isClosed.isOpen_compl⟩ @[simp, norm_cast] lemma coe_compl (s : CompactOpens α) : ↑sᶜ = (sᶜ : Set α) := rfl @[simp, norm_cast] lemma coe_himp (s t : CompactOpens α) : ↑(s ⇨ t) = (s ⇨ t : Set α) := rfl
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instHImp
null
instBooleanAlgebra : BooleanAlgebra (CompactOpens α) := SetLike.coe_injective.booleanAlgebra _ coe_sup coe_inf coe_top coe_bot coe_compl coe_sdiff coe_himp
instance
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
instBooleanAlgebra
null
@[simps toCompacts] map (f : α → β) (hf : Continuous f) (hf' : IsOpenMap f) (s : CompactOpens α) : CompactOpens β := ⟨s.toCompacts.map f hf, hf' _ s.isOpen⟩ @[simp, norm_cast]
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
map
The image of a compact open under a continuous open map.
coe_map {f : α → β} (hf : Continuous f) (hf' : IsOpenMap f) (s : CompactOpens α) : (s.map f hf hf' : Set β) = f '' s := rfl @[simp]
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_map
null
map_id (K : CompactOpens α) : K.map id continuous_id IsOpenMap.id = K := CompactOpens.ext <| Set.image_id _
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
map_id
null
map_comp (f : β → γ) (g : α → β) (hf : Continuous f) (hg : Continuous g) (hf' : IsOpenMap f) (hg' : IsOpenMap g) (K : CompactOpens α) : K.map (f ∘ g) (hf.comp hg) (hf'.comp hg') = (K.map g hg hg').map f hf hf' := CompactOpens.ext <| Set.image_comp _ _ _
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
map_comp
null
protected prod (K : CompactOpens α) (L : CompactOpens β) : CompactOpens (α × β) := { K.toCompacts.prod L.toCompacts with isOpen' := K.isOpen.prod L.isOpen } @[simp]
def
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
prod
The product of two `TopologicalSpace.CompactOpens`, as a `TopologicalSpace.CompactOpens` in the product space.
coe_prod (K : CompactOpens α) (L : CompactOpens β) : (K.prod L : Set (α × β)) = (K : Set α) ×ˢ (L : Set β) := rfl
theorem
Topology
[ "Mathlib.Topology.Sets.Closeds", "Mathlib.Topology.QuasiSeparated" ]
Mathlib/Topology/Sets/Compacts.lean
coe_prod
null
IsOpenCover {ι X : Type*} [TopologicalSpace X] (u : ι → Opens X) : Prop := iSup u = ⊤ variable {ι κ X Y : Type*} [TopologicalSpace X] {u : ι → Opens X} [TopologicalSpace Y] {v : κ → Opens Y}
def
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
IsOpenCover
An indexed family of open sets whose union is `X`.
mk (h : iSup u = ⊤) : IsOpenCover u := h
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
mk
null
of_sets {v : ι → Set X} (h_open : ∀ i, IsOpen (v i)) (h_iUnion : ⋃ i, v i = univ) : IsOpenCover (fun i ↦ ⟨v i, h_open i⟩) := by simp [IsOpenCover, h_iUnion]
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
of_sets
null
iSup_eq_top (hu : IsOpenCover u) : ⨆ i, u i = ⊤ := hu
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
iSup_eq_top
null
iSup_set_eq_univ (hu : IsOpenCover u) : ⋃ i, (u i : Set X) = univ := by simpa [← SetLike.coe_set_eq] using hu.iSup_eq_top
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
iSup_set_eq_univ
null
comap (hv : IsOpenCover v) (f : C(X, Y)) : IsOpenCover fun k ↦ (v k).comap f := by simp [IsOpenCover, ← preimage_iUnion, hv.iSup_set_eq_univ]
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
comap
Pullback of a covering of `Y` by a continuous map `X → Y`, giving a covering of `X` with the same index type.
exists_mem (hu : IsOpenCover u) (a : X) : ∃ i, a ∈ u i := by simpa [← hu.iSup_set_eq_univ] using mem_univ a
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
exists_mem
null
exists_mem_nhds (hu : IsOpenCover u) (a : X) : ∃ i, (u i : Set X) ∈ 𝓝 a := match hu.exists_mem a with | ⟨i, hi⟩ => ⟨i, (u i).isOpen.mem_nhds hi⟩
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
exists_mem_nhds
null
iUnion_inter (hu : IsOpenCover u) (s : Set X) : ⋃ i, s ∩ u i = s := by simp [← inter_iUnion, hu.iSup_set_eq_univ]
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
iUnion_inter
null
isTopologicalBasis (hu : IsOpenCover u) {B : ∀ i, Set (Set (u i))} (hB : ∀ i, IsTopologicalBasis (B i)) : IsTopologicalBasis (⋃ i, (Subtype.val '' ·) '' B i) := isTopologicalBasis_of_cover (fun i ↦ (u i).2) hu.iSup_set_eq_univ hB
lemma
Topology
[ "Mathlib.Topology.Sets.Opens" ]
Mathlib/Topology/Sets/OpenCover.lean
isTopologicalBasis
null
Opens where /-- The underlying set of a bundled `TopologicalSpace.Opens` object. -/ carrier : Set α /-- The `TopologicalSpace.Opens.carrier _` is an open set. -/ is_open' : IsOpen carrier
structure
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
Opens
The type of open subsets of a topological space.
instSecondCountableOpens [SecondCountableTopology α] (U : Opens α) : SecondCountableTopology U := inferInstanceAs (SecondCountableTopology U.1)
instance
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
instSecondCountableOpens
null
@[simp] carrier_eq_coe (U : Opens α) : U.1 = ↑U := rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
carrier_eq_coe
null
@[simp] coe_mk {U : Set α} {hU : IsOpen U} : ↑(⟨U, hU⟩ : Opens α) = U := rfl @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_mk
the coercion `Opens α → Set α` applied to a pair is the same as taking the first component
mem_mk {x : α} {U : Set α} {h : IsOpen U} : x ∈ mk U h ↔ x ∈ U := Iff.rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_mk
null
protected nonempty_coeSort {U : Opens α} : Nonempty U ↔ (U : Set α).Nonempty := Set.nonempty_coe_sort
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
nonempty_coeSort
null
protected nonempty_coe {U : Opens α} : (U : Set α).Nonempty ↔ ∃ x, x ∈ U := Iff.rfl @[ext] -- TODO: replace with `∀ x, x ∈ U ↔ x ∈ V`?
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
nonempty_coe
null
ext {U V : Opens α} (h : (U : Set α) = V) : U = V := SetLike.coe_injective h
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
ext
null
coe_inj {U V : Opens α} : (U : Set α) = V ↔ U = V := SetLike.ext'_iff.symm
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_inj
null
inclusion {U V : Opens α} (h : U ≤ V) : U → V := Set.inclusion h
abbrev
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
inclusion
A version of `Set.inclusion` not requiring definitional abuse
protected isOpen (U : Opens α) : IsOpen (U : Set α) := U.is_open' @[simp] theorem mk_coe (U : Opens α) : mk (↑U) U.isOpen = U := rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isOpen
null
Simps.coe (U : Opens α) : Set α := U initialize_simps_projections Opens (carrier → coe, as_prefix coe)
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
Simps.coe
See Note [custom simps projection].
@[simps] protected interior (s : Set α) : Opens α := ⟨interior s, isOpen_interior⟩ @[simp]
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
interior
The interior of a set, as an element of `Opens`.
mem_interior {s : Set α} {x : α} : x ∈ Opens.interior s ↔ x ∈ _root_.interior s := .rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_interior
null
gc : GaloisConnection ((↑) : Opens α → Set α) Opens.interior := fun U _ => ⟨fun h => interior_maximal h U.isOpen, fun h => le_trans h interior_subset⟩
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
gc
null
gi : GaloisCoinsertion (↑) (@Opens.interior α _) where choice s hs := ⟨s, interior_eq_iff_isOpen.mp <| le_antisymm interior_subset hs⟩ gc := gc u_l_le _ := interior_subset choice_eq _s hs := le_antisymm hs interior_subset
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
gi
The Galois coinsertion between sets and opens.
@[simp] mk_inf_mk {U V : Set α} {hU : IsOpen U} {hV : IsOpen V} : (⟨U, hU⟩ ⊓ ⟨V, hV⟩ : Opens α) = ⟨U ⊓ V, IsOpen.inter hU hV⟩ := rfl @[simp, norm_cast]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mk_inf_mk
null
coe_inf (s t : Opens α) : (↑(s ⊓ t) : Set α) = ↑s ∩ ↑t := rfl @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_inf
null
mem_inf {s t : Opens α} {x : α} : x ∈ s ⊓ t ↔ x ∈ s ∧ x ∈ t := Iff.rfl @[simp, norm_cast]
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_inf
null
coe_sup (s t : Opens α) : (↑(s ⊔ t) : Set α) = ↑s ∪ ↑t := rfl @[simp, norm_cast]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_sup
null
coe_bot : ((⊥ : Opens α) : Set α) = ∅ := rfl @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_bot
null
mem_bot {x : α} : x ∈ (⊥ : Opens α) ↔ False := Iff.rfl @[simp] theorem mk_empty : (⟨∅, isOpen_empty⟩ : Opens α) = ⊥ := rfl @[simp, norm_cast]
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_bot
null
coe_eq_empty {U : Opens α} : (U : Set α) = ∅ ↔ U = ⊥ := SetLike.coe_injective.eq_iff' rfl @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_eq_empty
null
mem_top (x : α) : x ∈ (⊤ : Opens α) := trivial @[simp, norm_cast]
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_top
null
coe_top : ((⊤ : Opens α) : Set α) = Set.univ := rfl @[simp] theorem mk_univ : (⟨univ, isOpen_univ⟩ : Opens α) = ⊤ := rfl @[simp, norm_cast]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_top
null
coe_eq_univ {U : Opens α} : (U : Set α) = univ ↔ U = ⊤ := SetLike.coe_injective.eq_iff' rfl @[simp, norm_cast]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_eq_univ
null
coe_sSup {S : Set (Opens α)} : (↑(sSup S) : Set α) = ⋃ i ∈ S, ↑i := rfl @[simp, norm_cast]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_sSup
null
coe_finset_sup (f : ι → Opens α) (s : Finset ι) : (↑(s.sup f) : Set α) = s.sup ((↑) ∘ f) := map_finset_sup (⟨⟨(↑), coe_sup⟩, coe_bot⟩ : SupBotHom (Opens α) (Set α)) _ _ @[simp, norm_cast]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_finset_sup
null
coe_finset_inf (f : ι → Opens α) (s : Finset ι) : (↑(s.inf f) : Set α) = s.inf ((↑) ∘ f) := map_finset_inf (⟨⟨(↑), coe_inf⟩, coe_top⟩ : InfTopHom (Opens α) (Set α)) _ _
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_finset_inf
null
@[simp, norm_cast] coe_iSup {ι} (s : ι → Opens α) : ((⨆ i, s i : Opens α) : Set α) = ⋃ i, s i := by simp [iSup]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_iSup
null
iSup_def {ι} (s : ι → Opens α) : ⨆ i, s i = ⟨⋃ i, s i, isOpen_iUnion fun i => (s i).2⟩ := ext <| coe_iSup s @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
iSup_def
null
iSup_mk {ι} (s : ι → Set α) (h : ∀ i, IsOpen (s i)) : (⨆ i, ⟨s i, h i⟩ : Opens α) = ⟨⋃ i, s i, isOpen_iUnion h⟩ := iSup_def _ @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
iSup_mk
null
mem_iSup {ι} {x : α} {s : ι → Opens α} : x ∈ iSup s ↔ ∃ i, x ∈ s i := by rw [← SetLike.mem_coe] simp @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_iSup
null
mem_sSup {Us : Set (Opens α)} {x : α} : x ∈ sSup Us ↔ ∃ u ∈ Us, x ∈ u := by simp_rw [sSup_eq_iSup, mem_iSup, exists_prop]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_sSup
null
frameMinimalAxioms : Frame.MinimalAxioms (Opens α) where inf_sSup_le_iSup_inf a s := (ext <| by simp only [coe_inf, coe_iSup, coe_sSup, Set.inter_iUnion₂]).le
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
frameMinimalAxioms
Open sets in a topological space form a frame.
instFrame : Frame (Opens α) := .ofMinimalAxioms frameMinimalAxioms
instance
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
instFrame
null
isOpenEmbedding' (U : Opens α) : IsOpenEmbedding (Subtype.val : U → α) := U.isOpen.isOpenEmbedding_subtypeVal
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isOpenEmbedding'
null
isOpenEmbedding_of_le {U V : Opens α} (i : U ≤ V) : IsOpenEmbedding (Set.inclusion <| SetLike.coe_subset_coe.2 i) where toIsEmbedding := .inclusion i isOpen_range := by rw [Set.range_inclusion i] exact U.isOpen.preimage continuous_subtype_val
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isOpenEmbedding_of_le
null
not_nonempty_iff_eq_bot (U : Opens α) : ¬Set.Nonempty (U : Set α) ↔ U = ⊥ := by rw [← coe_inj, coe_bot, ← Set.not_nonempty_iff_eq_empty]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
not_nonempty_iff_eq_bot
null
ne_bot_iff_nonempty (U : Opens α) : U ≠ ⊥ ↔ Set.Nonempty (U : Set α) := by rw [Ne, ← not_nonempty_iff_eq_bot, not_not]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
ne_bot_iff_nonempty
null
eq_bot_or_top {α} [t : TopologicalSpace α] (h : t = ⊤) (U : Opens α) : U = ⊥ ∨ U = ⊤ := by subst h; letI : TopologicalSpace α := ⊤ rw [← coe_eq_empty, ← coe_eq_univ, ← isOpen_top_iff] exact U.2
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
eq_bot_or_top
An open set in the indiscrete topology is either empty or the whole space.
IsBasis (B : Set (Opens α)) : Prop := IsTopologicalBasis (((↑) : _ → Set α) '' B)
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
IsBasis
A set of `opens α` is a basis if the set of corresponding sets is a topological basis.
isBasis_iff_nbhd {B : Set (Opens α)} : IsBasis B ↔ ∀ {U : Opens α} {x}, x ∈ U → ∃ U' ∈ B, x ∈ U' ∧ U' ≤ U := by constructor <;> intro h · rintro ⟨sU, hU⟩ x hx rcases h.mem_nhds_iff.mp (IsOpen.mem_nhds hU hx) with ⟨sV, ⟨⟨V, H₁, H₂⟩, hsV⟩⟩ refine ⟨V, H₁, ?_⟩ cases V dsimp at H₂ subst H₂ exact hsV · refine isTopologicalBasis_of_isOpen_of_nhds ?_ ?_ · rintro sU ⟨U, -, rfl⟩ exact U.2 · intro x sU hx hsU rcases @h ⟨sU, hsU⟩ x hx with ⟨V, hV, H⟩ exact ⟨V, ⟨V, hV, rfl⟩, H⟩
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isBasis_iff_nbhd
null
isBasis_iff_cover {B : Set (Opens α)} : IsBasis B ↔ ∀ U : Opens α, ∃ Us, Us ⊆ B ∧ U = sSup Us := by constructor · intro hB U refine ⟨{ V : Opens α | V ∈ B ∧ V ≤ U }, fun U hU => hU.left, ext ?_⟩ rw [coe_sSup, hB.open_eq_sUnion' U.isOpen] simp_rw [sUnion_eq_biUnion, iUnion, mem_setOf_eq, iSup_and, iSup_image] rfl · intro h rw [isBasis_iff_nbhd] intro U x hx rcases h U with ⟨Us, hUs, rfl⟩ rcases mem_sSup.1 hx with ⟨U, Us, xU⟩ exact ⟨U, hUs Us, xU, le_sSup Us⟩
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isBasis_iff_cover
null
IsBasis.isCompact_open_iff_eq_finite_iUnion {ι : Type*} (b : ι → Opens α) (hb : IsBasis (Set.range b)) (hb' : ∀ i, IsCompact (b i : Set α)) (U : Set α) : IsCompact U ∧ IsOpen U ↔ ∃ s : Set ι, s.Finite ∧ U = ⋃ i ∈ s, b i := by apply isCompact_open_iff_eq_finite_iUnion_of_isTopologicalBasis fun i : ι => (b i).1 · convert (config := {transparency := .default}) hb ext simp · exact hb'
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
IsBasis.isCompact_open_iff_eq_finite_iUnion
If `α` has a basis consisting of compact opens, then an open set in `α` is compact open iff it is a finite union of some elements in the basis
IsBasis.exists_finite_of_isCompact {B : Set (Opens α)} (hB : IsBasis B) {U : Opens α} (hU : IsCompact U.1) : ∃ Us ⊆ B, Us.Finite ∧ U = sSup Us := by classical obtain ⟨Us', hsub, hsup⟩ := isBasis_iff_cover.mp hB U obtain ⟨t, ht⟩ := hU.elim_finite_subcover (fun s : Us' ↦ s.1) (fun s ↦ s.1.2) (by simp [hsup]) refine ⟨Finset.image Subtype.val t, subset_trans (by simp) hsub, Finset.finite_toSet _, ?_⟩ exact le_antisymm (subset_trans ht (by simp)) (le_trans (sSup_le_sSup (by simp)) hsup.ge)
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
IsBasis.exists_finite_of_isCompact
null
IsBasis.le_iff {α} {t₁ t₂ : TopologicalSpace α} {Us : Set (Opens α)} (hUs : @IsBasis α t₂ Us) : t₁ ≤ t₂ ↔ ∀ U ∈ Us, IsOpen[t₁] U := by conv_lhs => rw [hUs.eq_generateFrom] simp [Set.subset_def, le_generateFrom_iff_subset_isOpen]
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
IsBasis.le_iff
null
isBasis_sigma {ι : Type*} {α : ι → Type*} [∀ i, TopologicalSpace (α i)] {B : ∀ i, Set (Opens (α i))} (hB : ∀ i, IsBasis (B i)) : IsBasis (⋃ i : ι, (fun U ↦ ⟨Sigma.mk i '' U.1, isOpenMap_sigmaMk _ U.2⟩) '' B i) := by convert TopologicalSpace.IsTopologicalBasis.sigma hB simp only [IsBasis, Set.image_iUnion, ← Set.image_comp] simp
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isBasis_sigma
null
IsBasis.of_isInducing {B : Set (Opens β)} (H : IsBasis B) {f : α → β} (h : IsInducing f) : IsBasis { ⟨f ⁻¹' U, U.2.preimage h.continuous⟩ | U ∈ B } := by simp only [IsBasis] at H ⊢ convert H.isInducing h ext; simp @[simp]
lemma
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
IsBasis.of_isInducing
null
isCompactElement_iff (s : Opens α) : CompleteLattice.IsCompactElement s ↔ IsCompact (s : Set α) := by rw [isCompact_iff_finite_subcover, CompleteLattice.isCompactElement_iff] refine ⟨?_, fun H ι U hU => ?_⟩ · introv H hU hU' obtain ⟨t, ht⟩ := H ι (fun i => ⟨U i, hU i⟩) (by simpa) refine ⟨t, Set.Subset.trans ht ?_⟩ rw [coe_finset_sup, Finset.sup_eq_iSup] rfl · obtain ⟨t, ht⟩ := H (fun i => U i) (fun i => (U i).isOpen) (by simpa using show (s : Set α) ⊆ ↑(iSup U) from hU) refine ⟨t, Set.Subset.trans ht ?_⟩ simp only [Set.iUnion_subset_iff] change ∀ i ∈ t, U i ≤ t.sup U exact fun i => Finset.le_sup
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
isCompactElement_iff
null
comap (f : C(α, β)) : FrameHom (Opens β) (Opens α) where toFun s := ⟨f ⁻¹' s, s.2.preimage f.continuous⟩ map_sSup' s := ext <| by simp only [coe_sSup, preimage_iUnion, biUnion_image, coe_mk] map_inf' _ _ := rfl map_top' := rfl @[simp]
def
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
comap
The preimage of an open set, as an open set.
comap_id : comap (ContinuousMap.id α) = FrameHom.id _ := FrameHom.ext fun _ => ext rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
comap_id
null
comap_mono (f : C(α, β)) {s t : Opens β} (h : s ≤ t) : comap f s ≤ comap f t := OrderHomClass.mono (comap f) h @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
comap_mono
null
coe_comap (f : C(α, β)) (U : Opens β) : ↑(comap f U) = f ⁻¹' U := rfl @[simp]
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
coe_comap
null
mem_comap {f : C(α, β)} {U : Opens β} {x : α} : x ∈ comap f U ↔ f x ∈ U := .rfl
theorem
Topology
[ "Mathlib.Order.Hom.CompleteLattice", "Mathlib.Topology.Compactness.Bases", "Mathlib.Topology.ContinuousMap.Basic", "Mathlib.Order.CompactlyGenerated.Basic", "Mathlib.Order.Copy" ]
Mathlib/Topology/Sets/Opens.lean
mem_comap
null