为什么世上没有免费午餐

my_ip = (require 'open-uri' ; open("http://myip.dk") { |f| /([0-9]{1,3}\.){3}[0-9]{1,3}/.match(f.read)[0].to_a[0] })

require 'open-uri'

open('http://myip.dk/'){|f|f.read.scan(/([0-9]{1,3}\.){3}[0-9]{1,3}/);puts $~}

require 'open-uri'
require 'rubygems'
require 'hpricot'

puts (Hpricot(open('http://myip.dk'))/"//td/font/b")[0].inner_html