mapErr<F> abstract method

Result<T, F> mapErr<F>(
  1. F mapper(
    1. E error
    )
)

Maps an error value and leaves successful values unchanged.

final readable = const Err<int, String>('bad')
    .mapErr((error) => 'error: $error');
final unchanged = const Ok<int, String>(42)
    .mapErr((error) => 'error: $error');

Implementation

Result<T, F> mapErr<F>(F Function(E error) mapper);