snippet: return value silliness

was shooting for the smallest, most extensible preferences class i could get. email me any comments—i’d like opinions on this.

 1  class Preference < ActiveRecord::Base
 2    belongs_to :user
 3    
 4    #FIXME descriptions should be in a config file?
 5    COMMON_DEFAULTS = {
 6      :email_on_message => [true,
 7        "Email when you get a message?"],
 8      :online_status_visible => [false,
 9        "Status visible to everyone?"],
10      :public_profile => [false,
11        "Full profile visible to everyone?"]
12      
13    }
14    
15    
16    class << self
17      def description_for(key)
18        (COMMON_DEFAULTS[key.to_sym] &&
19         COMMON_DEFAULTS[key.to_sym][1]) || 
20         nil 
21      end
22    end
23    
24  end