Function mask

pub fn mask<Conn, A>(
    conn: &Conn,
    operation: SO,
    destination_kind: SK,
    destination_window: Window,
    x_offset: i16,
    y_offset: i16,
    source_bitmap: A,
) -> Result<VoidCookie<'_, Conn>, ConnectionError>
where
    Conn: RequestConnection + ?Sized,
    A: Into<Pixmap>,