theorem Option.mem_iff {α : Type u_1} {a : α} {b : Option α} : a ∈ b ↔ b = some a

theorem Option.some_ne_none {α : Type u_1} (x : α) : some x ≠ none

theorem Option.forall {α : Type u_1} {p : Option α → Prop} : ((x : Option α) → p x) ↔ p none ∧ ((x : α) → p (some x))

theorem Option.exists {α : Type u_1} {p : Option α → Prop} : (∃ x, p x) ↔ p none ∨ ∃ x, p (some x)

theorem Option.get_mem {α : Type u_1} {o : Option α} (h : Option.isSome o = true) : Option.get o h ∈ o

theorem Option.get_of_mem {α : Type u_1} {a : α} {o : Option α} (h : Option.isSome o = true) : a ∈ o → Option.get o h = a

theorem Option.not_mem_none {α : Type u_1} (a : α) : ¬a ∈ none

@[simp]

theorem Option.some_get {α : Type u_1} {x : Option α} (h : Option.isSome x = true) : some (Option.get x h) = x

@[simp]

theorem Option.get_some {α : Type u_1} (x : α) (h : Option.isSome (some x) = true) : Option.get (some x) h = x

theorem Option.getD_of_ne_none {α : Type u_1} {x : Option α} (hx : x ≠ none) (y : α) : some (Option.getD x y) = x

theorem Option.mem_unique {α : Type u_1} {o : Option α} {a : α} {b : α} (ha : a ∈ o) (hb : b ∈ o) : a = b

theorem Option.ext {α : Type u_1} {o₁ : Option α} {o₂ : Option α} : (∀ (a : α), a ∈ o₁ ↔ a ∈ o₂) → o₁ = o₂

theorem Option.eq_none_iff_forall_not_mem : ∀ {α : Type u_1} {o : Option α}, o = none ↔ ∀ (a : α), ¬a ∈ o

@[simp]

theorem Option.isSome_none {α : Type u_1} : Option.isSome none = false

@[simp]

theorem Option.isSome_some : ∀ {α : Type u_1} {a : α}, Option.isSome (some a) = true

theorem Option.isSome_iff_exists : ∀ {α : Type u_1} {x : Option α}, Option.isSome x = true ↔ ∃ a, x = some a

@[simp]

theorem Option.isNone_none {α : Type u_1} : Option.isNone none = true

@[simp]

theorem Option.isNone_some : ∀ {α : Type u_1} {a : α}, Option.isNone (some a) = false

@[simp]

theorem Option.not_isSome : ∀ {α : Type u_1} {a : Option α}, Option.isSome a = false ↔ Option.isNone a = true

theorem Option.eq_some_iff_get_eq : ∀ {α : Type u_1} {o : Option α} {a : α}, o = some a ↔ ∃ h, Option.get o h = a

theorem Option.eq_some_of_isSome {α : Type u_1} {o : Option α} (h : Option.isSome o = true) : o = some (Option.get o h)

theorem Option.not_isSome_iff_eq_none : ∀ {α : Type u_1} {o : Option α}, ¬Option.isSome o = true ↔ o = none

theorem Option.ne_none_iff_isSome : ∀ {α : Type u_1} {o : Option α}, o ≠ none ↔ Option.isSome o = true

theorem Option.ne_none_iff_exists : ∀ {α : Type u_1} {o : Option α}, o ≠ none ↔ ∃ x, some x = o

theorem Option.ne_none_iff_exists' : ∀ {α : Type u_1} {o : Option α}, o ≠ none ↔ ∃ x, o = some x

theorem Option.bex_ne_none {α : Type u_1} {p : Option α → Prop} : (∃ x x_1, p x) ↔ ∃ x, p (some x)

theorem Option.ball_ne_none {α : Type u_1} {p : Option α → Prop} : ((x : Option α) → x ≠ none → p x) ↔ (x : α) → p (some x)

@[simp]

theorem Option.bind_some {α : Type u_1} (x : Option α) : Option.bind x some = x

@[simp]

theorem Option.bind_eq_some : ∀ {α : Type u_1} {b : α} {α_1 : Type u_2} {x : Option α_1} {f : α_1 → Option α}, Option.bind x f = some b ↔ ∃ a, x = some a ∧ f a = some b

@[simp]

theorem Option.bind_eq_none {α : Type u_1} {β : Type u_2} {o : Option α} {f : α → Option β} : Option.bind o f = none ↔ ∀ (b : β) (a : α), a ∈ o → ¬b ∈ f a

theorem Option.bind_comm {α : Type u_1} {β : Type u_2} {γ : Type u_3} {f : α → β → Option γ} (a : Option α) (b : Option β) : (Option.bind a fun x => Option.bind b (f x)) = Option.bind b fun y => Option.bind a fun x => f x y

theorem Option.bind_assoc {α : Type u_1} {β : Type u_2} {γ : Type u_3} (x : Option α) (f : α → Option β) (g : β → Option γ) : Option.bind (Option.bind x f) g = Option.bind x fun y => Option.bind (f y) g

theorem Option.join_eq_some : ∀ {α : Type u_1} {a : α} {x : Option (Option α)}, Option.join x = some a ↔ x = some (some a)

theorem Option.join_ne_none : ∀ {α : Type u_1} {x : Option (Option α)}, Option.join x ≠ none ↔ ∃ z, x = some (some z)

theorem Option.join_ne_none' : ∀ {α : Type u_1} {x : Option (Option α)}, ¬Option.join x = none ↔ ∃ z, x = some (some z)

theorem Option.join_eq_none : ∀ {α : Type u_1} {o : Option (Option α)}, Option.join o = none ↔ o = none ∨ o = some none

theorem Option.bind_id_eq_join {α : Type u_1} {x : Option (Option α)} : Option.bind x id = Option.join x

@[simp]

theorem Option.map_eq_map : ∀ {α α_1 : Type u_1} {f : α → α_1}, Functor.map f = Option.map f

theorem Option.map_none : ∀ {α α_1 : Type u_1} {f : α → α_1}, f <$> none = none

theorem Option.map_some : ∀ {α α_1 : Type u_1} {f : α → α_1} {a : α}, f <$> some a = some (f a)

@[simp]

theorem Option.map_eq_some' : ∀ {α : Type u_1} {b : α} {α_1 : Type u_2} {x : Option α_1} {f : α_1 → α}, Option.map f x = some b ↔ ∃ a, x = some a ∧ f a = b

theorem Option.map_eq_some : ∀ {α α_1 : Type u_1} {f : α → α_1} {x : Option α} {b : α_1}, f <$> x = some b ↔ ∃ a, x = some a ∧ f a = b

@[simp]

theorem Option.map_eq_none' : ∀ {α : Type u_1} {x : Option α} {α_1 : Type u_2} {f : α → α_1}, Option.map f x = none ↔ x = none

theorem Option.map_eq_none : ∀ {α α_1 : Type u_1} {f : α → α_1} {x : Option α}, f <$> x = none ↔ x = none

theorem Option.map_eq_bind {α : Type u_1} : ∀ {α : Type u_2} {f : α → α} {x : Option α}, Option.map f x = Option.bind x (some ∘ f)

theorem Option.map_congr {α : Type u_1} : ∀ {α : Type u_2} {f g : α → α} {x : Option α}, (∀ (a : α), a ∈ x → f a = g a) → Option.map f x = Option.map g x

@[simp]

theorem Option.map_id' {α : Type u_1} : Option.map id = id

@[simp]

theorem Option.map_map {β : Type u_1} {γ : Type u_2} {α : Type u_3} (h : β → γ) (g : α → β) (x : Option α) : Option.map h (Option.map g x) = Option.map (h ∘ g) x

theorem Option.comp_map {β : Type u_1} {γ : Type u_2} {α : Type u_3} (h : β → γ) (g : α → β) (x : Option α) : Option.map (h ∘ g) x = Option.map h (Option.map g x)

@[simp]

theorem Option.map_comp_map {α : Type u_1} {β : Type u_2} {γ : Type u_3} (f : α → β) (g : β → γ) : Option.map g ∘ Option.map f = Option.map (g ∘ f)

theorem Option.mem_map_of_mem {α : Type u_1} {β : Type u_2} {a : α} {x : Option α} (g : α → β) (h : a ∈ x) : g a ∈ Option.map g x

theorem Option.bind_map_comm {α : Type u_1} {β : Type u_2} {x : Option (Option α)} {f : α → β} : Option.bind x (Option.map f) = Option.bind (Option.map (Option.map f) x) id

theorem Option.join_map_eq_map_join {α : Type u_1} {β : Type u_2} {f : α → β} {x : Option (Option α)} : Option.join (Option.map (Option.map f) x) = Option.map f (Option.join x)

theorem Option.join_join {α : Type u_1} {x : Option (Option (Option α))} : Option.join (Option.join x) = Option.join (Option.map Option.join x)

theorem Option.mem_of_mem_join {α : Type u_1} {a : α} {x : Option (Option α)} (h : a ∈ Option.join x) : some a ∈ x

@[simp]

theorem Option.some_orElse {α : Type u_1} (a : α) (x : Option α) : (HOrElse.hOrElse (some a) fun x => x) = some a

@[simp]

theorem Option.none_orElse {α : Type u_1} (x : Option α) : (HOrElse.hOrElse none fun x => x) = x

@[simp]

theorem Option.orElse_none {α : Type u_1} (x : Option α) : (HOrElse.hOrElse x fun x => none) = x

@[simp]

theorem Option.guard_eq_some : ∀ {α : Type u_1} {p : α → Prop} {a b : α} [inst : DecidablePred p], Option.guard p a = some b ↔ a = b ∧ p a

theorem Option.liftOrGet_eq_or_eq {α : Type u_1} {f : α → α → α} (h : ∀ (a b : α), f a b = a ∨ f a b = b) (o₁ : Option α) (o₂ : Option α) : Option.liftOrGet f o₁ o₂ = o₁ ∨ Option.liftOrGet f o₁ o₂ = o₂

@[simp]

theorem Option.liftOrGet_none_left {α : Type u_1} {f : α → α → α} {b : Option α} : Option.liftOrGet f none b = b

@[simp]

theorem Option.liftOrGet_none_right {α : Type u_1} {f : α → α → α} {a : Option α} : Option.liftOrGet f a none = a

@[simp]

theorem Option.liftOrGet_some_some {α : Type u_1} {f : α → α → α} {a : α} {b : α} : Option.liftOrGet f (some a) (some b) = some (f a b)

theorem Option.elim_none {β : Sort u_1} {α : Type u_2} (x : β) (f : α → β) : Option.elim none x f = x

theorem Option.elim_some {β : Sort u_1} {α : Type u_2} (x : β) (f : α → β) (a : α) : Option.elim (some a) x f = f a

@[simp]

theorem Option.getD_map {α : Type u_1} {β : Type u_2} (f : α → β) (x : α) (o : Option α) : Option.getD (Option.map f o) (f x) = f (Option.getD o x)

noncomputable def Option.choice (α : Type u_1) : Option α

An arbitrary some a with a : α if α is nonempty, and otherwise none.

Equations

• Option.choice α = if h : Nonempty α then some (Classical.choice h) else none

theorem Option.choice_eq {α : Type u_1} [Subsingleton α] (a : α) : Option.choice α = some a

theorem Option.choice_isSome_iff_nonempty {α : Type u_1} : Option.isSome (Option.choice α) = true ↔ Nonempty α

@[simp]

theorem Option.to_list_some {α : Type u_1} (a : α) : Option.toList (some a) = [a]

@[simp]

theorem Option.to_list_none (α : Type u_1) : Option.toList none = []