English
The filter defined by mkOfClosure has its sets exactly equal to S, provided hs holds.
Русский
Фильтр, построенный через mkOfClosure, имеет множества ровно как в S, при условии hs.
LaTeX
$$$\\mathrm{sets}(\\mathrm{mkOfClosure}(S, H)) = S$$$
Lean4
/-- `mkOfClosure s hs` constructs a filter on `α` whose elements set is exactly
`s : Set (Set α)`, provided one gives the assumption `hs : (generate s).sets = s`. -/
protected def mkOfClosure (s : Set (Set α)) (hs : (generate s).sets = s) : Filter α
where
sets := s
univ_sets := hs ▸ univ_mem
sets_of_superset := hs ▸ mem_of_superset
inter_sets := hs ▸ inter_mem