cattr_accessor vs class_attribute

cattr_accessor_vs_class_attribute

[1] pry(main)> class Base
[1] pry(main)*   cattr_accessor :setting2
[1] pry(main)* end
=> [:setting2]

[2] pry(main)> class Subclass < Base ; end
=> nil
[3] pry(main)> Base.setting2
=> nil
[4] pry(main)> Base.setting2 = true
=> true
[5] pry(main)> Subclass.setting2
=> true
[6] pry(main)> Subclass.setting2 = false
=> false
[7] pry(main)> Base.setting2
=> false
継承ルート一個で同じクラス変数を共有する普通のclass変数のaccessor



[8] pry(main)> class Base
[8] pry(main)*   class_attribute :setting
[8] pry(main)* end
=> [:setting]

[9] pry(main)> class Subclass < Base ; end
=> nil
[10] pry(main)> Base.setting
=> nil
[11] pry(main)> Base.setting = true
=> true
[12] pry(main)> Subclass.setting
=> true
[13] pry(main)> Subclass.setting = false
=> false
[14] pry(main)> Base.setting
=> true
クラス毎のクラスインスタンス変数のaccessor