English
There is a TendstoIxxClass structure for Icc with respect to nhds a under OrderTopology α.
Русский
Существует структура TendstoIxxClass для Icc относительно nhds a в OrderTopology α.
LaTeX
$$$\\text{TendstoIxxClass }\\mathrm{Set.Icc} \\ (nhds(a))\\ (nhds(a))$$$
Lean4
instance tendstoIccClassNhds [OrderTopology α] (a : α) : TendstoIxxClass Icc (𝓝 a) (𝓝 a) :=
by
simp only [nhds_eq_order, iInf_subtype']
refine ((hasBasis_iInf_principal_finite _).inf (hasBasis_iInf_principal_finite _)).tendstoIxxClass fun s _ => ?_
refine ((ordConnected_biInter ?_).inter (ordConnected_biInter ?_)).out <;> intro _ _
exacts [ordConnected_Ioi, ordConnected_Iio]