errToNullable method
E?
errToNullable()
Creates an E?
value from this
. Useful when converting an error and
passing it as argument where a nullable type is expected, e.g.,
third-party libraries that expect nullable types.
Anti-patterns
This method should not be used to match only the Err case, e.g.:
final Result<int, String> result = Ok(42);
final errorText = result.errToNullable();
if (errorText != null) {
print(errorText);
}
Instead, use pattern matching for that:
final Result<int, String> result = Ok(42);
if (foo case Err(e: final errorText)) {
print(errorText);
}
Implementation
E? errToNullable() => switch (this) {
Ok() => null,
Err(:E e) => e,
};