Rails 3 implementation of .none scope

gistfile1.rb

module ActiveRecord
  class Base
    class << self
      if respond_to? :none
        puts "ActiveRecord::Base already has a method 'none'. Remove the implementation from #{__FILE__}"
      else
        # In Rails 4 this creates a noop query. Until then, use a query that never returns data.
        def none
          where '1=2'
        end
      end
    end
  end
end