# Collect mmethods redefined in 'self' with `visibility >= min_visibility`.
	fun collect_redef_mmethods(filter: ModelFilter): Set[MMethod] do
		var res = new HashSet[MMethod]
		for mproperty in collect_redef_mproperties(filter) do
			if not filter.accept_mentity(mproperty) then continue
			if mproperty isa MMethod then res.add(mproperty)
		end
		return res
	end