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57ecb5f7ba
As discussed in the PR for the Result pattern implementation (https://github.com/flutter/website/pull/11444) @parlough recommended that `asError` and `asOk` should be not be used, and instead we should use proper exhaustiveness checking. This PR removes the two "convenience" methods and refactors code. In some cases, it was enough with writing a proper `if` clause, while in others it was necessary to use a `switch`. Still, they are present in the `testing` folder, as they can be useful for testing purposes. ## Pre-launch Checklist - [x] I read the [Flutter Style Guide] _recently_, and have followed its advice. - [x] I signed the [CLA]. - [x] I read the [Contributors Guide]. - [x] I have added sample code updates to the [changelog]. - [x] I updated/added relevant documentation (doc comments with `///`). If you need help, consider asking for advice on the #hackers-devrel channel on [Discord]. <!-- Links --> [Flutter Style Guide]: https://github.com/flutter/flutter/blob/master/docs/contributing/Style-guide-for-Flutter-repo.md [CLA]: https://cla.developers.google.com/ [Discord]: https://github.com/flutter/flutter/blob/master/docs/contributing/Chat.md [Contributors Guide]: https://github.com/flutter/samples/blob/main/CONTRIBUTING.md [changelog]: ../CHANGELOG.md
49 lines
1.1 KiB
Dart
49 lines
1.1 KiB
Dart
// Copyright 2024 The Flutter team. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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/// Utility class to wrap result data
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///
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/// Evaluate the result using a switch statement:
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/// ```dart
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/// switch (result) {
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/// case Ok(): {
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/// print(result.value);
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/// }
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/// case Error(): {
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/// print(result.error);
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/// }
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/// }
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/// ```
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sealed class Result<T> {
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const Result();
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/// Creates a successful [Result], completed with the specified [value].
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const factory Result.ok(T value) = Ok._;
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/// Creates an error [Result], completed with the specified [error].
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const factory Result.error(Exception error) = Error._;
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}
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/// Subclass of Result for values
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final class Ok<T> extends Result<T> {
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const Ok._(this.value);
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/// Returned value in result
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final T value;
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@override
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String toString() => 'Result<$T>.ok($value)';
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}
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/// Subclass of Result for errors
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final class Error<T> extends Result<T> {
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const Error._(this.error);
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/// Returned error in result
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final Exception error;
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@override
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String toString() => 'Result<$T>.error($error)';
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}
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