python/pycharm type hinting with base class?

Question

the base class here is actually an abstract class provides basic methods with type hints, and the subclasses overwrite them with the same parameters.

i tried the below code, wanted to let values in dictionary mp hint these basic methods but it doesn't work.

from typing import Dict

class Base:
    pass

class A(Base):
    pass

class B(Base):
    pass


mp: Dict[str, Base] = {
    "A": A,
    "B": B
}

the Pycharm IDE warned Expected type 'Dict[str, Base]', got 'Dict[str, Union[A, B]]' instead.

i wonder what the correct way is

https://stackoverflow.com/questions/46092104/subclass-in-type-hinting — MaxNoe, May 07 '20 at 04:14
thank you @MaxNoe it worked. i should try searching sub class instead of base class — Rainy Chan, May 07 '20 at 07:17

score 4 · Accepted Answer · answered May 07 '20 at 07:22

4

as the above friend @MaxNoe mentioned, i should use the code below

from typing import Dict, Type

class Base:
    pass

class A(Base):
    pass

class B(Base):
    pass


mp: Dict[str, Type[Base]] = {
    "A": A,
    "B": B
}

answered May 07 '20 at 07:22

Rainy Chan

109
7

python/pycharm type hinting with base class?

1 Answers1