<doc>  <parent>    <discarded>      <discarded/>    </discarded>    <preserved/>    This text node must be discarded    <discarded>      <discarded/>    </discarded>    <preserved>      content1      <child1></child1>      <child2>content2</child2>      <preserved>too</preserved>      <child2>content3</child2>      <preserved></preserved>      <child2>content4</child2>      <preserved/>      <child2>content5</child2>      content6    </preserved>    This text node must be discarded    <discarded>      <discarded/>    </discarded>    This text node must be discarded    <preserved></preserved>    This text node must be discarded    <preserved/>    This text node must be discarded    <discarded>      <discarded/>    </discarded>    This text node must be discarded  </parent></doc>