Currently, decorated private methods are not settable. This is inline with the general behavior of private methods, which are implemented as private slots which can be read but not updated. However, this limits some of their potential use cases - for instance it is not possible currently to make a @bound decorator which would work with private methods.

One possibility would be to allow decorated methods to have a set value on their access object. This would allow private method initializers added via addInitializer to update the value of the method, allowing them to do pretty much the same things as public method decorators. However, this could also make the implementation of private methods a bit more complex and possibly less performant.