xml=[==[
<?xml version='1.0'?>
<doc >doctxt<!-- comment at doc level -->
  <text>doctxt tag    ttt </text>
  <foo >
    <bar /><!-- comment at foo level -->
    <bar max='1' />
    <bar />
    <bar max='2' />
  </foo>
  <foo id='xx1'>foo2a
    <attributes id='zz'>dummy attr tag</attributes>
    <bar id='xx2' />
    <bar id='xx3' max='3' />
    <bar ><![CDATA[cdata at bar level]]></bar>
    <bar max='4' ><?ProgInst blah blah blah ?></bar>
    <bar id='xx4' max='5' />
    foo2b
  </foo>
</doc>
<?ProgInst after doc element ?>