I did notice that Data::Dumper does nearly the same thing you're trying to do ... and I'm trying to figure out how to get Data::Dumper's output to "thaw" back into a usable perl variable. Perhaps someone else will answer this. 

my $a = [qw{v1 v2}];
my %h = (
         k1 => {
             k11 => $a,
             k12 => 'w00t!',
         },
         k2 => {
             k21 => 'what?',
             k22 => $a,
         },
        );

use Data::Dumper;
#print Dumper(\%h);

my $h2; $h2 = {
          'k2' => {
                    'k21' => 'what?',
                    'k22' => [
                               'v1',
                               'v2'
                             ]
                  },
          'k1' => {
                    'k11' => $h2->{'k2'}{'k22'},
                    'k12' => 'w00t!'
                  }
};

print Dumper($h2);

[download]
The first hash, %h, is what you're trying to do, but in a manner that works. Then I dump it, and I pasted that output back into the code and dump the new hash-ref, $h2. But it doesn't want to work, and I'm not sure what bits of trickery are needed to get it to work - probably some Data::Dumper variables when dumping, but I'm not sure offhand.

In reply to Re: Populating a nested hash with itself? by Tanktalus
in thread Populating a nested hash with itself? by jkva

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