How about this: 
$root->first_child->sort_children_on_att("type");
sort_my_kids($root);

$twig->print;
#----------
sub sort_my_kids{
    my $me = shift;
    $me->sort_children_on_value;
    foreach my $kid($me->children){
        sort_my_kids($kid); # Recursive
    }    
}

[download]
Prints: 
<enhancement>
  <descriptorgroup>
    <descriptors controlled="y" type="DRG">
      <mainterm weight="a">aspirin</mainterm>
      <mainterm>panadol</mainterm>
      <mainterm>xenon</mainterm>
      <mainterm weight="a">zorro</mainterm>
    </descriptors>
    <descriptors controlled="y" type="MED">
      <descriptor>
        <mainterm>disease</mainterm>
        <mainterm>pestilence</mainterm>
        <mainterm weight="a">plague</mainterm>
      </descriptor>
    </descriptors>
  </descriptorgroup>
</enhancement>

[download]

     Theory is when you know something, but it doesn't work.
    Practice is when something works, but you don't know why it works.
    Programmers combine Theory and Practice: Nothing works and they don't know why.         -Anonymous

In reply to Re: twig inbuilt methods to sort whole xml tree by NetWallah
in thread twig inbuilt methods to sort whole xml tree by bharathinc

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.