twitter_check_username_availability.rb

require 'net/https'
require 'uri'

usernames_to_check = %W(macedo _macedo)
available = []

usernames_to_check.each do |username|
  uri = URI.parse "https://twitter.com/#{username}"

  http = Net::HTTP.new uri.host, uri.port
  http.use_ssl = true
  http.verify_mode = OpenSSL::SSL::VERIFY_NONE

  request = Net::HTTP::Get.new(uri.request_uri)
  response = http.request(request)

  available.push(username) if response.code == 404
end

puts available.empty? ? 'unavailable' : available.join(', ')