Question

I want to tell inherited methods apart from overloaded or newly defined methods. Is that possible with Python?

Example:

class A(object):
  def spam(self):
    print 'A spam'
  def ham(self):
    print 'A ham'

class B(A):
  def spam(self):
    print 'Overloaded spam'
  def eggs(self):
    print 'Newly defined eggs'

Desired functionality:

>>> magicmethod(B.spam)
'overloaded'
>>> magicmethod(B.ham)
'inherited'
>>> magicmethod(B.eggs)
'newly defined'

Is there a “magic method” like in the example, or some way to tell those types of method implementations apart?

Answer 1

I’m not sure it’s a good idea, but you can probably do it by using hasattr and __dict__.

def magicmethod(clazz, method):
    if method not in clazz.__dict__:  # Not defined in clazz : inherited
        return 'inherited'
    elif hasattr(super(clazz), method):  # Present in parent : overloaded
        return 'overloaded'
    else:  # Not present in parent : newly defined
        return 'newly defined'