[issue44192] Annotations, Inheritance and Circular Reference

[Filipe Laíns]

Filipe Laíns <lains at riseup.net> added the comment:

The annotations will effectively become strings, instead of object references, in Python 3.11, which solves this issue.

You can enable this behavior in holder Python version with `from __future__ import annotations`, see PEP 563[1].

>>> class Base:
...     _sub: list[Sub]
...
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in Base
NameError: name 'Sub' is not defined


>>> from __future__ import annotations
>>> class Base:
...     _sub: list[Sub]
...
>>> class Sub:
...     _parent: Base
...
>>>

[1] https://www.python.org/dev/peps/pep-0563/

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nosy: +FFY00

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