ActiveSupport::Callbacks

延續上一篇，這邊用 ActiveSupport::Callbacks 來做 callbacks

官方教學：

http://api.rubyonrails.org/classes/ActiveSupport/Callbacks.html


下一個問題：

所以怎麼做到下面這個效果呢？

```ruby

class Test

extend ActiveModel::Callbacks

define_model_callbacks :execute

after_execute :log_something, only: [:index]

def index

puts "Hi World!"

end

def log_something

puts "Log something..."

end

end

```

或者是：

```ruby

class Test

include ActiveSupport::Callbacks

define_callbacks :execute

after_execute :log_something, only: [:index]

def index

puts "Hi World!"

end

def log_something

puts "Log something..."

end

end

```
呢？