Thank you Dear, your coding is fentastic. This solution is working. Even I did my code as below. But my code was specific to elements.Here is my code

#!/usr/bin/perl
use strict;
use warnings;
use XML::Twig;

my (@sortedM, @sortedL);
my $i=0;
my $twig= new XML::Twig(twig_handlers => { 
                                'enhancement' => sub {$_->first_child-
+>sort_children_on_att("type");},
                                'descriptor' => \&sortSubEltsHandler,
                            },
                        pretty_print => 'indented',    
            keep_atts_order => 1,
            );            
$twig->parse(\*DATA); 
$twig->print;
$twig->purge;

sub sortSubEltsHandler
{     
    my( $t,$elt)= @_;
    my $root= $t->root;    
    my @mainterms = $root->descendants(q{mainterm});
       @sortedM = reverse sort { $a->text cmp $b->text }
        @mainterms;
    my @links = $root->descendants(q{link});
       @sortedL =reverse sort { $a->text cmp $b->text }
        @links;
    $elt->cut_children;
    foreach my $mainterm (@sortedM) {
    my $new_elt= XML::Twig::Elt->new($mainterm->name => $mainterm->tex
+t);
    $new_elt->paste($elt);
    }
    foreach my $link (@sortedL) {
    my $new_elt= XML::Twig::Elt->new($link->name => $link->text);
    $new_elt->paste($elt);
    }
}#end of sortSubEltsHandler

__DATA__
<enhancement>
<descriptorgroup>
<descriptors type="MED" controlled="y">
<descriptor>
<mainterm weight="a">plague</mainterm>
<mainterm>disease</mainterm>
<mainterm>pestilence</mainterm>
<link>f</link>
<link>C</link>
<link>M</link>
</descriptor>
</descriptors>
<descriptors type="DRG" controlled="y">
<descriptor>
<mainterm>panadol</mainterm>
<mainterm weight="a">zorro</mainterm>
<mainterm>xenon</mainterm>
<mainterm weight="a">aspirin</mainterm>
<link>b</link>
<link>P</link>
<link>z</link>
</descriptor>
</descriptors>
</descriptorgroup>
</enhancement>

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In reply to Re^4: twig inbuilt methods to sort whole xml tree by bharathinc
in thread twig inbuilt methods to sort whole xml tree by bharathinc

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