ruby - Why are callbacks callable in Rails model classes? -

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मेरे पास इस तरह रेल मॉडल मॉडल वर्ग है: 

  class something & lt; ActiveRecord :: बेस से पहले self.key = secureRandom.urlsafe_base64 (8) एंड एंड   
 मैं यहाँ  before_create  क्यों कॉल कर सकता हूं? मुझे यह  ActiveRecord :: Base  की एक विधि होने की उम्मीद थी लेकिन यह नहीं है कॉलबैक  ActiveRecord :: कॉलबैक  के तरीकों हैं। लेकिन मैं उन्हें बिना किसी वर्ग के मॉडल क्लास में क्यों कॉल कर सकता हूं?   
 
 
 आप ऐसा कर सकते हैं क्योंकि  ActiveRecord :: बेस  ऐसा करता है (या आपके रेल के आपके संस्करण के आधार पर ऐसा कुछ):  
  Base.class_eval करें # ... कॉलबैक, एक्टिवमोडेल :: अवलोकन, टाइमस्टैम्प # ... एंड   
 तो  ActiveRecord :: Base  में पहले से ही  ActiveRecord :: Callbacks  शामिल है और आपका क्लास इनहेरीटिंग द्वारा कॉलबैक को उठाता है से  ActiveRecord :: बेस ।

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