On 10/29/2022 1:45 PM, Paulo da Silva wrote:
Hi!
Consider this simple script ...
___________________
from typing import List, Optional
class GLOBALS:
foos=None
class Foo:
def __init__(self):
pass
class Foos:
Foos: List[Foo]=[]
# SOME GLOBALS ARE USED HERE in a real script
def __init__(self):
pass
GLOBALS.foos: Optional[Foos]=Foos()
___________________
Running mypy on it:
pt9.py:18: error: Type cannot be declared in assignment to non-self
attribute
pt9.py:18: error: Incompatible types in assignment (expression has type
"Foos", variable has type "None")
Line 18 is last line and pt9.py is the scrip.
Replacing last line by
GLOBALS.foos=Foos()
and running mypy still gives the second error.
pt9.py:18: error: Incompatible types in assignment (expression has type
"Foos", variable has type "None")
What is the common practice in these cases?
Thank you.
I don't understand
class Foos:
Foos: List[Foo]=[]
If "Foos" is supposed to be a class attribute, then it cannot have the
same name as the class. Perhaps you meant the class to be named "Foo".
Then a class attribute of Foos: List[Foo]=[] might barely make sense.
Even then, remember that each instance of Foo would only know about the
same (originally empty) list Foos. Is that really what you want?
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