//please include function withMargin.

static int showForm_defaultGap = 4;
static int showForm_gapBetweenColumns = 10;

static JPanel showFormTitled(fS title, fO... _parts) {
  ret swing(func -> JPanel {
    final new Var<JFrame> frame;
    JPanel panel = showForm_makePanel(frame, _parts);
    frame.set(showForm_makeFrame(title, panel));
    ret panel;
  });
}

static JPanel showForm_makePanel(final Var<JFrame> frame, O... _parts) {
  Pair<LL<JComponent>, Runnable> p = showForm_makeComponents(frame, _parts);
  LL<JComponent> l = p.a;
  Runnable submit = p.b;
  
  int minW = showForm_leftWidth(l);
  new L<JComponent> out;
  for (L<JComponent> row : l)
    out.add(westAndCenter(withRightMargin(showForm_gapBetweenColumns, jMinWidth(minW, first(row))), second(row)));
  JPanel panel = vstackWithSpacing(out, showForm_defaultGap);
  
  ret panel;
}