python / python/cpython

dataclass with slots=True, init=False raises AttributeError

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#98,247 8 comments 1 reaction 1 assignee View on GitHub

@ericvsmith is already working on this.

Since Oct 30, 2022.

stdlib topic-dataclasses type-bug
Dominant language
Python
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Description

Python 3.10.4
dataclass with slots=True, init=False raises AttributeError on attribute access

from dataclasses import dataclass

@dataclass(slots=True, init=False)
class WorldState:
    is_mission_running: bool = False

w = WorldState()
w.is_mission_running

Traceback (most recent call last):
File "", line 1, in
AttributeError: 'WorldState' object has no attribute 'is_mission_running'

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