# `GSPenProtocol append:`

*Instance Method*

Appends the contents of another pen to this pen.

## Declaration

```swift
func append(_ pen: (any GSPenProtocol & NSObjectProtocol)!)
```

```objc
- (void) append:(NSObject<GSPenProtocol> *) pen;
```

```python
append_(pen: NSObject<GSPenProtocol>)
```

## Discussion

Requires that the other pen is of the same type as this pen in the general case. Specific pen implementations may also accept pen arguments of other types.