Function std::gui_message_box

generic<T> void gui_message_box(
    &GuiUi ui,
    const &char title,
    const &char text,
    int buttons,
    fn void(&Widget, int, ?&T) onClose,
    ?&T userData,
)

A standard message box: 'text' and a row of buttons (GUI_MB_* bits), shown modally. onClose(dialog, result) runs once a button (result GUI_RESULT_*) or Escape (GUI_RESULT_CANCEL) closed it; the box frees itself afterwards. The buttons are named "yes", "no", "ok" and "cancel" (Widget::find).