Does the use of $memfile as a memory file actually buy you anything, stevieb? I can't see how what you have there differs from the simpler alternative:

use warnings;
use strict;

use Data::Dumper;

my $href = {
    a => 1,
    b => [
            2,
            3,
         ],
    c => {
            25 => 'y',
            26 => 'z',
         },
    d => 4,
};

my $text = Dumper ($href);
print $text;
[download]

What am I missing?