HL7 message construction

#Creating an HL7 v2.6 message
#Nikos Vaggalis, www.i-programmer.info
##http://www.i-programmer.info/programming/perl/9920-health-level-7-hl7-with-perl.html
#license:Artistic 1.0

use Net::HL7::Message;
use Net::HL7::Segment;
use Net::HL7::Segments::MSH;
use Time::Piece;
use strict;

$Net::HL7::HL7_VERSION='2.6';

#####DATA INIT

my $msh_9=["ADT","A01","ADT_A01"];
my $msh_10=201;
my $msh_22="DD015";

my $pid_3= [
              "100660325",["NationalPN","2.16.840.1.113883.19.3","ISO"],"0"
              ."~"."80253",'','','','',1
           ];
my $pid_5=["GREENING","WAYNE",'','','','',"L"];
my $pid_7="30/01/1961";
my $pid_8="M";
my $pid_19=303603715;
my $pid_23="LONDON";

my $pv1_2="E";
my $pv1_7=12345678901;
my $pv1_18=0;
my $pv1_19=185;
my $pv1_20=0;

my @dg1data=([1,"S42.1"],[2,"S42.2"]);

my $msg = new Net::HL7::Message();

#####MSH SEGMENT
my $msh = new Net::HL7::Segments::MSH();
   $msh->setField(7, $msh->getField(7)."+0200");
   $msh->setField(9, $msh_9);
   $msh->setField(10, "id".$msh_10);
   $msh->setField(11, "P");
   $msh->setField(22, $msh_22);
$msg->addSegment($msh);

#####PID SEGMENT
my $pid = new Net::HL7::Segment("PID");
   $pid->setField(3,  $pid_3);
   $pid->setField(5,  $pid_5);

my $time = Time::Piece->strptime($pid_7,'%d/%m/%Y');
   $time= $time->strftime('%Y%m%d');
   $pid->setField(7,  $time);

   $pid->setField(8,  $pid_8);
   $pid->setField(19, $pid_19);
   $pid->setField(23, $pid_23);
$msg->addSegment($pid);

#####PV1 SEGMENT
my $pv1 = new Net::HL7::Segment("PV1");
   $pv1->setField(2, $pv1_2);
   $pv1->setField(7, $pv1_7);
   $pv1->setField(18, $pv1_18);
   $pv1->setField(19, $pv1_19);
   $pv1->setField(20, $pv1_20);

$msg->addSegment($pv1);


for (my $i=0;$i<=$#dg1data;$i++) {
    my $dg = new Net::HL7::Segment("DG1");
       $dg->setField(1, $dg1data[$i]->[0]);
       $dg->setField(3, $dg1data[$i]->[1]);
       $msg->addSegment($dg);
};


print $msg->toString();