# Using "tie".

use Tie::Hash::Inheriting ();

{
   tie(my %data, 'Tie::Hash::Inheriting');

   %data = (
      Colour  => 'blue',
      Entries => {
         Flowers => {
            Dahlia => { Smell  => 'nice' },
            Rose   => { Colour => 'red'  },
         },
      },
   );

   print
      $data{'Entries'}{'Flowers'}{'Rose'  }{'Colour'}, $/,  # red
      $data{'Entries'}{'Flowers'}{'Dahlia'}{'Colour'}, $/;  # blue

   untie(%data);  # Free mem. %data going out of scope is not enough.
}