Ruby On Rails in UA/Разработка на ROR/Array.sort проблемка!

>> a = ["a", "z", "b"]
=> ["a", "z", "b"]
>> a.class
=> Array

>> a.sort
=> ["a", "b", "z"]

>> c = City.find(:first)
=> #<City id: 5, name: "Москва", created_at: "2009-07-01 14:32:08", updated_at: "2009-07-01 14:32:44">
>> c.stations
=> [#<Station id: 7, name: "Войковская", city_id: 5, created_at: "2009-07-01 16:29:20", updated_at: "2009-07-01 16:29:20">, #<Station id: 8, name: "Китай город", city_id: 5, created_at: "2009-07-01 16:29:33", updated_at: "2009-07-01 16:29:33">]
>> c.stations.class
=> Array

>> c.stations.sort
NoMethodError: undefined method `<=>' for #<Station:0x58a7b4>

class Station
    def <=>other
        self.name<=>other.name
    end
end