Description

JukkaL

opened on May 21, 2015

Issue body actions

The following program prints __main__.A[int] even though A is not generic. I'd expect it to print something like <class '__main__.A'>.

from typing import Iterator

class A(Iterator[int]):
    def __next__(self): pass

print(A().__class__)

Also, this does not generate an exception, even though A is not generic:

def f(x: A[int]) -> None: pass

Activity

1. JukkaL

   changed the title [-]Confusing __class__ for instance of non-generic class that subclasses generic clsas[/-] [+]Confusing __class__ for instance of non-generic class that subclasses generic class[/+] on May 21, 2015
2. gvanrossum

   added

   bug

   on May 21, 2015
3. gvanrossum

   self-assigned this

   on May 21, 2015
4. gvanrossum commented on May 21, 2015

   

   gvanrossum

   on May 21, 2015

   Member

   More actions

   I'm on the fence about calling this a bug. What I implemented in rev 25af77d is that no matter how you instantiate A, you always get the original class A as the instance's __class__. And that is what's happening here. It just so happens that the actual class A remembers its parameters. Regarding using A[int] later, that probably shouldn't be allowed -- I need to rework the logic here. This is also related to issue #115. I will have to come back to this later.
5. benjaminp

   unassigned

   gvanrossum

   on Jan 23, 2016
6. gvanrossum

   added this to the 3.5.2 milestone on Apr 4, 2016
7. gvanrossum commented on Apr 4, 2016

   

   gvanrossum

   on Apr 4, 2016

   Member

   More actions

   OK, fixed by #195.
8. gvanrossum

   closed this as completedon Apr 4, 2016

Issue actions