Throughout Hoon School, you have been using `%.y` and `%.n`, often implicitly, every time you have asked a question like `?: =(5 4)`. The `=()` expression returns a loobean, a member of the type union `?(%.y %.n)`. (There is a proper aura `@f` but unfortunately it can't be used outside of the compiler.) These can also be written as `&` (`%.y`, true) and `|` (`%.n`, false), which is common in older code but should be avoided for clarity in your own compositions.