Function mg::question

pub fn question<CALLBACK, COMM, SETT, WIDGET>(
    mg: &StreamHandle<<Mg<COMM, SETT> as Update>::Msg>,
    relm: &Relm<WIDGET>,
    msg: String,
    choices: &'static [char],
    callback: CALLBACK
)where
    CALLBACK: Fn(Option<String>) -> WIDGET::Msg + 'static,
    COMM: Clone + EnumFromStr + EnumMetaData + SpecialCommand + 'static,
    SETT: Default + EnumMetaData + Settings + SettingCompletion + 'static,
    WIDGET: Widget + 'static,

Ask a multiple-choice question to the user.