constructor
case h
α : Type u
inst✝ : DecidableEq α
as : Array α
a : α
⊢ (∀ (a_1 : α), a_1 ∈ as → a_1 ≠ a) ↔ ¬a ∈ as
case h.mp
α : Type u
inst✝ : DecidableEq α
as : Array α
a : α
⊢ (∀ (a_1 : α), a_1 ∈ as → a_1 ≠ a) → ¬a ∈ as

case h.mpr
α : Type u
inst✝ : DecidableEq α
as : Array α
a : α
⊢ ¬a ∈ as → ∀ (a_2 : α), a_2 ∈ as → a_2 ≠ a