Is it possible to update an another atom from a selector?

[rafaeltuelho]

I want to update another atom from inside a selector/atom set function. Given AtomA and SelectorB whenever I update SelectorB I want to update AtomA.
Is it possible? If yes is it considered an anti-pattern?

[drarmstr]

Yes, it is possible to update multiple upstream atoms or selectors from a writeable selector's set callback.