Zulip Chat Archive
Stream: mathlib4
Topic: Intersecting all sets in a filter
Kevin Buzzard (Jul 22 2024 at 10:37):
The notation for Set.sInter
won't eat a filter directly:
import Mathlib.Order.Filter.Basic
open Filter
example (A : Set 𝓧) : ⋂₀ (𝓟 A) = A := sorry -- doesn't compile
example (A : Set 𝓧) : ⋂₀ (𝓟 A).sets = A := sorry -- works fine
Would it be desirable/possible to extend this notation so that it applied to filters and returned a set?
Yaël Dillies (Jul 22 2024 at 10:39):
Last updated: May 02 2025 at 03:31 UTC