I am using XML:twig to extract some attributes from an XML file using Perl;
Here is my code: 
use XML::Twig;
my $file = $ARGV[0];
$file =~ /(.+)\.xml/;
my $outfile = $1.".snp" ;
open my $out,'>',$outfile or die "Could not open file '$outfile' $!";
my $twig = XML::Twig->new
(
twig_handlers => 
    {
        'Rs/MergeHistory' => \&MergeHistory,
    }
);
 $twig -> parsefile( "$file");
sub MergeHistory 
    {
        my ($twig, $elt) = @_;
        print $out "\t";
        print $out "rs";
                print $out $elt->att('rsId'), ",";
        print $out "b";
        print $out $elt->att('buildId'), ",";
    }

[download]
This print the following results:

rs56546490,b130,    rs386588736,b142
rs56546490,b130,    rs386588736,b142

What I want is to print each MergeHistory rsId and buildId together as the following:

rs56546490,rs386588736,   b130,b142
rs56546490,rs386588736,   b130,b142

Here is a part of the XML file which contains on two MergeHistory tags :

<Rs>
<MergeHistory rsId="56546490" buildId="130">
<MergeHistory rsId="386588736" buildId="142">
</Rs>
<Rs>
<MergeHistory rsId="56546490" buildId="130">
<MergeHistory rsId="386588736" buildId="142">
</Rs>

In reply to Print attributes from two tags together by AhmedABdo

Title:
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