Today, I was reading RH's Descriptor HowTo Guide at
https://docs.python.org/3/howto/descriptor.html?highlight=descriptors
I just really want to fully "get" this.
So I put together a little test from scratch. Looks like this:
class The:
class Answer:
def __get__(self, obj, type=None):
return 42
>>> The.Answer
<class '__main__.The.Answer'>
>>>
but, I expected to see 42.
So, digging deeper I read:
For classes, the machinery is in type.__getattribute__() which transforms
B.x into B.__dict__['x'].__get__(None, B). In pure Python, it looks like:
def __getattribute__(self, key):
"Emulate type_getattro() in Objects/typeobject.c"
v = object.__getattribute__(self, key)
if hasattr(v, '__get__'):
return v.__get__(None, self)
return v
OK, so I copied this function, then ran it and got:
>>> __getattribute__(The, 'Answer')
42
So, what I don't get is why the "B.x into B.__dict__['x'].__get__(None, B)"
part doesn't work in my case.
I'm sure I'm missing something here (that`s usually the case for me <:‑|) ,
but what?
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