__getattr__相当于方法

Question

When an attribute is not found object.__getattr__ is called. Is there an equivalent way to intercept undefined methods?

Answer 1

There is no difference. A method is also an attribute. (If you want the method to have an implicit "self" argument, though, you'll have to do some more work to "bind" the method).

Answer 2

Methods are attributes too. __getattr__ works the same for them:

class A(object):

  def __getattr__(self, attr):
    print attr

Then try:

>>> a = A()
>>> a.thing
thing
>>> a.thing()
thing
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'NoneType' object is not callable

Answer 3

you didn't return anything.

class A(object):

  def __getattr__(self, attr):
    return attr

should work