completelyNormalSpace_iff_forall_isOpen_normalSpace

∀ {X : Type u_1} [inst : TopologicalSpace X], CompletelyNormalSpace X ↔ ∀ (s : Set X), IsOpen s → NormalSpace ↑s

A space is completely normal iff all open subspaces are normal.

Defined in: Mathlib.Topology.Separation.Regular
Cited by: 3 results in Mathlib
Foundations: Depth 75 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes: TopologicalSpace

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