Source code for returns.pointfree.bind_ioresult

from __future__ import annotations

from typing import TYPE_CHECKING, Callable, TypeVar

from returns.interfaces.specific.ioresult import IOResultLikeN
from returns.primitives.hkt import Kinded, KindN, kinded

if TYPE_CHECKING:
    from returns.io import IOResult  # noqa: WPS433

_FirstType = TypeVar('_FirstType')
_SecondType = TypeVar('_SecondType')
_ThirdType = TypeVar('_ThirdType')
_UpdatedType = TypeVar('_UpdatedType')

_IOResultLikeKind = TypeVar('_IOResultLikeKind', bound=IOResultLikeN)


[docs]def bind_ioresult( function: Callable[[_FirstType], 'IOResult[_UpdatedType, _SecondType]'], ) -> Kinded[Callable[ [KindN[_IOResultLikeKind, _FirstType, _SecondType, _ThirdType]], KindN[_IOResultLikeKind, _UpdatedType, _SecondType, _ThirdType], ]]: """ Composes successful container with a function that returns a container. In other words, it modifies the function's signature from: ``a -> IOResult[b, c]`` to: ``Container[a, c] -> Container[b, c]`` .. code:: python >>> from returns.io import IOResult, IOSuccess >>> from returns.context import RequiresContextIOResult >>> from returns.pointfree import bind_ioresult >>> def returns_ioresult(arg: int) -> IOResult[int, str]: ... return IOSuccess(arg + 1) >>> bound = bind_ioresult(returns_ioresult) >>> assert bound(IOSuccess(1)) == IOSuccess(2) >>> assert bound( ... RequiresContextIOResult.from_value(1), ... )(...) == IOSuccess(2) """ @kinded def factory( container: KindN[ _IOResultLikeKind, _FirstType, _SecondType, _ThirdType, ], ) -> KindN[_IOResultLikeKind, _UpdatedType, _SecondType, _ThirdType]: return container.bind_ioresult(function) return factory