use Data::Dumper;
use Tie::SortHash;
 
%hash = ( 
x=> 'line 1',
z=> [ 1, 2, 4],
y=> { file=> 'test.txt',
      length=> 200,
      type => 'ASCII'
    },
a=> 'line 2'
);
tie %hash, 'Tie::SortHash', \%hash;
print Dumper(\%hash);
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