Function of_night 

pub(crate) fn of_night(
    needs: &Needs,
    night: Date,
    zone: &TimeZone,
    days: &Days,
) -> (String, bool)

The alarm at the end of night’s night, for its row on the page: when it rings (“07:00”), and whether “No alarm” was asked; (“”, false) when none would ring (no morning ticked, the night taken out).