Stupid Decorator Tricks

broken.py

class Foo(object):
  def __init__(self):
    self.value = 5

def wrap(param):
  def _wrap(clss):
    class _Wrap(clss):
      def __init__(self):
        super(_Wrap, self).__init__()
        self.other_value = param
    return _Wrap
  return _wrap

@wrap(10)
class Bar(Foo):
  def __init__(self):
    super(Bar, self).__init__()

b = Bar() # crashes on line 17 as it recursively calls `Bar.__init__`
print(b.value, b.other_value)

works.py

class Foo(object):
  def __init__(self):
    self.value = 5

def wrap(param):
  def _wrap(clss):
    class _Wrap(clss):
      def __init__(self):
        super(_Wrap, self).__init__()
        self.other_value = param
    return _Wrap
  return _wrap

@wrap(10)
class Bar(Foo):
  def __init__(self):
    super().__init__()

b = Bar()
print(b.value, b.other_value) # prints `5 10`