require 'ipaddr' module Irrc module Prefix private def classify_by_protocol(prefixes) prefixes.each_with_object(Struct.new(:ipv4, :ipv6).new([], [])) {|prefix, result| addr = IPAddr.new(prefix) if addr.ipv4? result.ipv4 << prefix elsif addr.ipv6? result.ipv6 << prefix end } end end end