stateManager.CurrentChangeSet = ChangeSetKey.Initial;

S>      StateManager stateManager = new StateManager();
S>      StatefulCollection<int> values = new StatefulCollection<int>(stateManager);

S>      ChangeSetKey changeSet0 = stateManager.NewChangeSet("adding 0"); // AnnounceChanges?
S>      values.Add(0);

S>      ChangeSetKey changeSet1 = stateManager.NewChangeSet("adding 1");
S>      values.Add(1); // values: { 0, 1 }

S>      stateManager.CurrentChangeSet = changeSet0; // values: { 0 }
S>      stateManager.CurrentChangeSet = changeSet1; // values: { 0, 1 }
S>

      StateManager stateManager = new StateManager();
      StatefulCollection<int> values = new StatefulCollection<int>(stateManager);

      ChangeSetKey changeSet0 = stateManager.NewChangeSet("adding 0"); // AnnounceChanges?
      values.Add(0);

      ChangeSetKey changeSet1 = stateManager.NewChangeSet("adding 1");
      values.Add(1); // values: { 0, 1 }

      stateManager.CurrentChangeSet = changeSet0; // values: { 0 }
      stateManager.CurrentChangeSet = changeSet1; // values: { 0, 1 }
      valuse.Add(2); // можно так?
      ChangeSetKey changeSet2 = stateManager.newChangeSet("Adding x");
      values.Add(3);
      stateManager.CurrentChangeSet = changeSet1; // values: ???

      stateManager.CurrentChangeSet = changeSet0; // values: { 0 }
      valuse.Add(2); // можно так?
      ChangeSetKey changeSet2 = stateManager.newChangeSet("Adding x");
      values.Add(3);
      stateManager.CurrentChangeSet = changeSet0; // values: ???
      stateManager.CurrentChangeSet = changeSet1; // а здесь какая-то ошибка должна быть?

      StateManager stateManager = new StateManager();
      StatefulCollection<int> values = new StatefulCollection<int>(stateManager);
      Edit edit1 = stateManager.beginEdit("adding 0"); // Announce edit
      values.Add(0);

      Edit edit2 = stateManager.beginEdit("adding 1, 2"); // Announce edit
      values.Add(1);
      Checkpoint checkpoint2_1 = stateManager.getState("state {0, 1}");
      values.Add(2);

      stateManager.ResumeEdit(edit1); // values: {0}, edit: edit1
      stateManager.ResumeEdit(edit2); // values: {0, 1, 2} edit: edit2
      values.Add(3);
      Edit edit3 = stateManager.beginEdit("Last edit");
      values.Add(4);
      stateManager.ResumeEdit(edit2); //values : {0, 1, 2, 3}, Edit имеет "автоматическую" границу
      values.Add(6);
      stateManager.ResumeEdit(edit3); //Ошибка - нельзя делать redo, хвост операции потерян
      Edit curEdit = stateManager.continueFromCheckpoint(checkpoint2_1); // curEdit == edit2, values : {0, 1}
      stateManager.ResumeEdit(edit2); // Неочевидный момент, values = {0, 1, 2, 3}
      Edit curEdit1 = stateManager.continueFromCheckpoint(checkpoint2_1); // curEdit1 == edit2, values : {0, 1}
      values.Add(7);
      stateManager.ResumeEdit(edit1); // values: {0}, edit: edit1
      stateManager.ResumeEdit(edit2); // values: {0, 1, 7} edit: edit2
      stateManager.continueFromCheckpoint(checkpoint2_1); // edit2, values : {0, 1}      
      Edit dummyEdit = stateManager.beginEdit("Dummy edit");
      values.Add(8);
      stateManager.continueFromCheckpoint(checkpoint2_1); // edit2, values : {0, 1}      
      stateManager.ResumeEdit(edit2); // values: {0, 1} edit: edit2
      stateManager.ResumeEdit(dummyEdit); // values: {0, 1, 8} edit: dummyEdit

      stateManager.CurrentChangeSet = changeSet0; // values: { 0 }
      stateManager.CurrentChangeSet = changeSet1; // values: { 0, 1 }
      valuse.Add(2); // можно
      ChangeSetKey changeSet2 = stateManager.newChangeSet("Adding x");
      values.Add(3);
      stateManager.CurrentChangeSet = changeSet1; // values: {0, 1, 2}

      stateManager.CurrentChangeSet = changeSet0; // values: { 0 }
      valuse.Add(2); // можно
      ChangeSetKey changeSet2 = stateManager.newChangeSet("Adding x");
      values.Add(3);
      stateManager.CurrentChangeSet = changeSet0; // values: { 0 }
      stateManager.CurrentChangeSet = changeSet1; // InvalidOperationException
M>