| // Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import 'package:analyzer/dart/element/element.dart'; |
| |
| /// The result of attempting to resolve an identifier to a element. |
| class ResolutionResult { |
| /// An instance that can be used anywhere that no element was found. |
| static const ResolutionResult none = |
| ResolutionResult._(_ResolutionResultState.none); |
| |
| /// An instance that can be used anywhere that multiple elements were found. |
| static const ResolutionResult ambiguous = |
| ResolutionResult._(_ResolutionResultState.ambiguous); |
| |
| /// The state of the result. |
| final _ResolutionResultState state; |
| |
| /// The element that was found, or `null` if the [state] is not |
| /// [_ResolutionResultState.single]. |
| final ExecutableElement element; |
| |
| /// Initialize a newly created result to represent resolving to a single |
| /// [element]. |
| ResolutionResult(this.element) |
| : assert(element != null), |
| state = _ResolutionResultState.single; |
| |
| /// Initialize a newly created result with no element and the given [state]. |
| const ResolutionResult._(this.state) : element = null; |
| |
| /// Return `true` if this result represents the case where multiple ambiguous |
| /// elements were found. |
| bool get isAmbiguous => state == _ResolutionResultState.ambiguous; |
| |
| /// Return `true` if this result represents the case where no element was |
| /// found. |
| bool get isNone => state == _ResolutionResultState.none; |
| |
| /// Return `true` if this result represents the case where a single element |
| /// was found. |
| bool get isSingle => state == _ResolutionResultState.single; |
| } |
| |
| /// The state of a [ResolutionResult]. |
| enum _ResolutionResultState { |
| /// Indicates that no element was found. |
| none, |
| |
| /// Indicates that a single element was found. |
| single, |
| |
| /// Indicates that multiple ambiguous elements were found. |
| ambiguous |
| } |