# Search groups named `name` from paths `lookpaths`.
	private fun search_group_in_paths(name: String, lookpaths: Collection[String]): ArraySet[MGroup]
	do
		var res = new ArraySet[MGroup]
		for dirname in lookpaths do
			# try a single group directory
			var mg = identify_group(dirname/name)
			if mg != null then
				res.add mg
			end
		end
		return res
	end