AR#to_json に こなたｗ

rails 
 9    #   konata = User.find(1) 
10    #   konata.to_json 
11    # 
12    #   {"id": 1, "name": "Konata Izumi", "age": 16, 
13    #    "created_at": "2006/08/01", "awesome": true}

こなたｗｗｗｗ

15    # The :only and :except options can be used to limit the attributes 
16    # included, and work similar to the #attributes method. For example: 
17    # 
18    #   konata.to_json(:only => [ :id, :name ]) 
19    # 
20    #   {"id": 1, "name": "Konata Izumi"} 
21    # 
22    #   konata.to_json(:except => [ :id, :created_at, :age ]) 
23    # 
24    #   {"name": "Konata Izumi", "awesome": true}

ほうほう、AR#to_json に :only と :except がつけられるのかー。良いことを知った。
あと :include もあるのね。で、:include でも :only とかが使えると。