Is this dumb?

add_rotator.rb

def add_rotator_to(hash)
  hash.define_singleton_method :rotator do
    inject({}) do |rotated, key_value|
      if key_value.first =~ /_rotate/
        rotated.merge key_value.first[0..-8].to_sym => self[key_value.first].rotate!.first
      else
        rotated.merge key_value.first => key_value.last
      end
    end
  end
end

>> a = { :foo => "bar", :baz_rotate => [ "que", "quz" ] }                                                                                                                                                                                                                       
=> {:foo=>"bar", :baz_rotate=>["que", "quz"]}
>> add_rotator_to a
=> #<Proc:0x007fd91fcbc640@/Users/bill/Projects/strands/spec/factories.rb:32 (lambda)>
>> a.rotator
=> {:foo=>"bar", :baz=>"quz"}
>> a
=> {:foo=>"bar", :baz_rotate=>["quz", "que"]}
>> a.rotator
=> {:foo=>"bar", :baz=>"que"}
>> a
=> {:foo=>"bar", :baz_rotate=>["que", "quz"]}
>>