Method swap

returns/future.py:674–694

Swaps value and error types. So, values become errors and errors become values. It is useful when you have to work with errors a lot. And since we have a lot of ``.bind_`` related methods and only a single ``.lash``. It is easier to work with values

(self)

        return IOResult.from_result(await self._inner_value)

    def swap(self) -> 'FutureResult[_ErrorType_co, _ValueType_co]':
        """
        Swaps value and error types.

        So, values become errors and errors become values.
        It is useful when you have to work with errors a lot.
        And since we have a lot of ``.bind_`` related methods
        and only a single ``.lash``.
        It is easier to work with values than with errors.

        .. code:: python

          >>> import anyio
          >>> from returns.future import FutureSuccess, FutureFailure
          >>> from returns.io import IOSuccess, IOFailure

          >>> assert anyio.run(FutureSuccess(1).swap) == IOFailure(1)
          >>> assert anyio.run(FutureFailure(1).swap) == IOSuccess(1)

        """
        return FutureResult(_future_result.async_swap(self._inner_value))

    def map(
        self,