Some sample data would come in handy.

I would try a search function that takes a ref and uses ref to see if it is a hash, array or scalar. Then use that info to decide if it is what you're looking for, and if not, recurse on the contents. Eventually, return either undef, or a reference to the element in the structure you wanted and go from there.

For debugging, I'd suggest Dumpering the structure to a file, and building a string in the recursion to show where you are at the moment for printing useful comments.

It can also be handy to indent your prints to follow the recursion.

findthing($root, '$root->', '');

sub findthing
{
  my $node = shift;
  my $debugString = shift;
  my $indent = shift;
  if (ref $node eq 'ARRAY')
  {
    for (0..$#$node)
    {
      my $result = findthing($node->[$_], $debugString . "\[$_\]", $in
+dent .'  ');
      return $result if defined $result;
    }
    print $indent . "No luck in array at $debugString\n";
  }elsif (ref $node eq 'HASH')
  {
    for (keys %$node)
    {
      my $result = findthing($node->{$_}, $debugString . "\{$_\}", $in
+dent . '  ');
      return $result if defined $result;   
    }
    print $indent . "No luck in hash at $debugString\n";
  }
...
  return undef;
}
[download]