fork download 
  1. class TheMeta(type):
  2.     def __init__(cls, name, bases, dct):
  3.         def _myInit(self, *args, **kwargs):
  4.             if type(self) is cls:
  5.                 print "_myInit of {} {} ({})".format(name, self, id(self.__init__))
  6.                 cls._origInit(self, *args, **kwargs)
  7.                 cls._afterInit(self)
  8.             else:
  9.                 cls._origInit(self, *args, **kwargs)
  10.  
  11.         def _afterInit(self):
  12.             print "Init has passed..."
  13.             # Do some magic here...
  14.  
  15.         cls._origInit = cls.__init__
  16.         cls.__init__ = _myInit
  17.         cls._afterInit = _afterInit
  18.         super(TheMeta, cls).__init__(name, bases, dct)
  19.  
  20. class TheBase(object):
  21.     __metaclass__ = TheMeta
  22.  
  23. class MyDerived(TheBase):
  24.     def __init__(self, great=False):
  25.         TheBase.__init__(self)
  26.         print "MyDerived __init__ of {} ({})".format(self, id(self.__init__))
  27.  
  28. class MyDerived2(MyDerived):
  29.     def __init__(self):
  30.         MyDerived.__init__(self, great=True)
  31.         print "MyDerived2 __init__ of {} ({})".format(self, id(self.__init__))
  32.  
  33. sd = MyDerived()
  34. d2 = MyDerived2()
Success #stdin #stdout 0.01s 8968KB
comments (?)
stdin 
Standard input is empty
stdout 
_myInit of MyDerived <__main__.MyDerived object at 0xb743180c> (3076893508)
MyDerived __init__ of <__main__.MyDerived object at 0xb743180c> (3076599932)
Init has passed...
_myInit of MyDerived2 <__main__.MyDerived2 object at 0xb74318ac> (3076893508)
MyDerived __init__ of <__main__.MyDerived2 object at 0xb74318ac> (3074621068)
MyDerived2 __init__ of <__main__.MyDerived2 object at 0xb74318ac> (3076599932)
Init has passed...
https://ideone.com/XSK7OE
language:
Python (cpython 2.7.16)
created:
9 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!