Why does comparing methods with `is` always return False?

Asked Apr 09 '20 at 15:28

Active May 19 '20 at 19:20

Viewed 160 times

Why does this return False

>>> class A:
...     def a_method(self):
...         pass
...     def b(self):
...         print(self.a_method is self.a_method)
... 
>>> c = A()
>>> c.b()
False
>>> c.a_method is c.a_method
False

when you can use is for functions

>>> def a(): pass
... 
>>> a is a
True

asked Apr 09 '20 at 15:28

Boris Verkhovskiy

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:D most obscure indeed: `id(c.a) == id(c.a)` but not `c.a is c.a` – user2390182 Apr 09 '20 at 15:31
seems that `id(self.a_method)` returns a different value everytime... `==` works – Jean-François Fabre Apr 09 '20 at 15:31
`id(c.a) == id(c.a)` is not an indication that it's the same. id can be reused – Jean-François Fabre Apr 09 '20 at 15:32
Also see this: https://stackoverflow.com/questions/18264578 – Tom Zych Apr 09 '20 at 15:34
2

and this https://stackoverflow.com/questions/15977808/why-dont-methods-have-reference-equality – Boris Verkhovskiy Apr 09 '20 at 15:35

Why does comparing methods with `is` always return False?

0 Answers0