# Returns a `HashSet[String]` containing every mapping keys in the current
	# `Bundle`
	fun keys: HashSet[String]
	do
		var javastring_set = native_bundle.key_set
		var string_set = new HashSet[String]

		for element in javastring_set do
			string_set.add(element.to_s)
		end

		return string_set
	end