let button = |
#on_press: fn(e: null) -> Any = |_| null,
#width: &Length = &`Shrink,
#height: &Length = &`Shrink,
#padding: &Padding = &`All(5.0),
#disabled: &bool = &false,
child: &Widget
| -> Widget `Button({ child, on_press: &on_press, width, height, padding, disabled })