# `GSLayer.undoManager`

*Instance Property*

The undo manager of the containing glyph when the layer belongs to that glyph.

## Declaration

```swift
var undoManager: UndoManager? { get }
```

```objc
@property (nonatomic, readonly) NSUndoManager * undoManager;
```

```python
undoManager() -> NSUndoManager
```

## See Also

### Undo

- [`GSLayer.undoManagerCheck`](/Core/GlyphsCore/GSLayer/undoManagerCheck) — The undo manager of the containing glyph when undo registration is enabled.