Rails: Don't override initialize on ActiveRecord objects

ActiveRecord::Base doesn't always use new to create objects, so initialize might not be called. I wanted to use a Hash on an ActiveRecord::Base subclass to store some calculated values, so I naively did this: class User < ActiveRecord::Base def initialize(args = nil) super @my_cache = {} end endHowever I quickly ran into some "You have a nil object when you didn't expect it!" issues. Some debugger

[kkumma]

super

[suginoy]

"Digging in the source revealed that the instantiate method in active_record/base.rb uses allocate to create classes rather than new."

[n0ts]

ActiveRecord でオブジェクトを作成したとき initialize メソッドはオーバーライドしようにする、かわりに after_initialize メソッドでフックすること