// Copyright (c) 2023, 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.

/// A mixin for marking classes.
mixin Markable {
  bool _isMarked = false;

  bool mark() {
    if (_isMarked) return false;
    _isMarked = true;
    return true;
  }

  bool get isMarked => _isMarked;

  void unmark() {
    _isMarked = false;
  }
}