svoid <A> comboBoxDynamicToolTip(JComboBox<A> cb, IF1<A, S> makeToolTip) {
  class ComboBoxRendererWithToolTip extends javax.swing.plaf.basic.BasicComboBoxRenderer {
    public Component getListCellRendererComponent(JList list, O value, int index, bool isSelected, bool cellHasFocus) {
      super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
      if (isSelected)
        setToolTipText(makeToolTip?.get((A) value));
      this;
    }
  }
  
  cb.setRenderer(new ComboBoxRendererWithToolTip);
}