Why does `getattr` not support consecutive attribute retrievals?

Question

class A(): pass

a = A()
b = A()

a.b = b
b.c = 1

a.b     # this is b
getattr(a, \"b\") # so is this

a.b.c   # this is 1   
getattr(a, \"b.c\") # this raises an Attrib         


        

Answer 1

I think the most straight forward way to achieve what you want is to use operator.attrgetter.

>>> import operator
>>> class B():
...   c = 'foo'
... 
>>> class A():
...   b = B()
... 
>>> a = A()
>>> operator.attrgetter('b.c')(a)
'foo'

If the attribute doesn't exist then you'll get an AttributeError

>>> operator.attrgetter('b.d')(a)
Traceback (most recent call last):
  File "", line 1, in 
AttributeError: B instance has no attribute 'd'