Source code for returns.primitives.container
from abc import ABCMeta
from typing import Any, TypeVar, Union
from typing_extensions import TypedDict
from returns.interfaces.equable import Equable
from returns.primitives.hkt import Kind1
from returns.primitives.types import Immutable
_EqualType = TypeVar('_EqualType', bound=Equable)
class _PickleState(TypedDict):
"""Dict to represent the `BaseContainer` state to be pickled."""
# TODO: Remove `__slots__` from here when `slotscheck` allow ignore classes
# by using comments. We don't need the slots here since this class is just
# a representation of a dictionary and should not be instantiated by any
# means.
# See: https://github.com/ariebovenberg/slotscheck/issues/71
__slots__ = ('container_value',) # type: ignore
container_value: Any
[docs]class BaseContainer(Immutable, metaclass=ABCMeta):
"""Utility class to provide all needed magic methods to the context."""
__slots__ = ('_inner_value',)
_inner_value: Any
[docs] def __init__(self, inner_value) -> None:
"""
Wraps the given value in the Container.
'value' is any arbitrary value of any type including functions.
"""
object.__setattr__(self, '_inner_value', inner_value) # noqa: WPS609
[docs] def __repr__(self) -> str:
"""Used to display details of object."""
return '<{0}: {1}>'.format(
self.__class__.__qualname__.strip('_'),
str(self._inner_value),
)
[docs] def __eq__(self, other: Any) -> bool:
"""Used to compare two 'Container' objects."""
return container_equality(self, other) # type: ignore
[docs] def __hash__(self) -> int:
"""Used to use this value as a key."""
return hash(self._inner_value)
[docs] def __getstate__(self) -> _PickleState:
"""That's how this object will be pickled."""
return {'container_value': self._inner_value} # type: ignore
[docs] def __setstate__(self, state: Union[_PickleState, Any]) -> None:
"""Loading state from pickled data."""
if isinstance(state, dict) and 'container_value' in state:
object.__setattr__( # noqa: WPS609
self, '_inner_value', state['container_value'],
)
else:
# backward compatibility with 0.19.0 and earlier
object.__setattr__(self, '_inner_value', state) # noqa: WPS609
[docs]def container_equality(
self: Kind1[_EqualType, Any],
other: Kind1[_EqualType, Any],
) -> bool:
"""
Function to compare similar containers.
Compares both their types and their inner values.
"""
if type(self) != type(other): # noqa: WPS516, E721
return False
return bool(
self._inner_value == other._inner_value, # type: ignore # noqa: WPS437
)