48 lines
1.1 KiB
Dart
48 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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