#!/usr/bin/perl -w
use strict;
use Tree::DAG_Node;

my $tree =
[
        [
            'Node1'
        ],
        [
                [ 'GrandChild1' ],
                [ 'GrandChild2' ],
            'Node2'
        ],
  'Root'
];

my $dagnode= Tree::DAG_Node->lol_to_tree($tree);
print map {"$_\n"} @{ $dagnode->draw_ascii_tree };


__END__
And the output is:

                |
              <Root>
   /-----------------\
   |                 |
<Node1>           <Node2>
              /-------------\
              |             |
        <GrandChild1> <GrandChild2>