Function chargrid_event_routine::side_effect_then

pub fn side_effect_then<F, D, V, U>(
    f: F
) -> impl EventRoutine<Return = U::Return, Data = U::Data, View = U::View, Event = U::Event> where
    U: EventRoutine<Data = D, View = V>,
    F: FnOnce(&mut D) -> U,