mapErr<F extends Object> method
Maps a Result<T, E>
to Result<T, F>
by applying a function to
a contained Err
value, leaving an Ok
value untouched.
This function can be used to pass through a successful result while handling an error.
Implementation
Future<Result<T, F>> mapErr<F extends Object>(F Function(E) op) =>
then((result) => result.mapErr(op));