Hello , I am struggling to write code to implement a doubly link list. Could any of you please help me with it. This is what I have written so far. If you could point me to any material which shows how a doubly linked list is implemented in PErl that will be of great help to me... 

#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my $head= undef; ## reference to first node
my $tail=\$head;  ## reference to the "next" field of the last node 
my $list;

open FILE, "<datastored.txt" or die $!;

# Creating a doubly linked list

while (<FILE>){
    my $node = {
                "data" => $_ , 
                "next" => undef,
                "prev" => undef,
            };
   
    $$tail=$node;   
    $node->{"prev"}= $tail;
    $tail = \$node->{"next"};
    
}


print Dumper $head;

&print_list($head);

sub print_list {
    $list=$_[0];
        while ($list) {
        print Dumper $list;
        print "$list->{data}";
        $list = $list->{next};        
        }

}

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In reply to Doubly link list implementation by punitpawar

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