# Code from the perldoc
use Memoize;
use Memoize::Expire;
use DB_File;

# Set up persistence
tie my %disk_cache => 'DB_File', $filename, O_CREAT|O_RDWR, 0666];

# Set up expiration policy, supplying persistent hash as a target
tie my %cache => 'Memoize::Expire',
                 LIFETIME => $lifetime,    # In seconds
                 NUM_USES => $n_uses,
                 HASH => \%disk_cache;

# Set up memoization, supplying expiring persistent hash for cache
memoize 'function', SCALAR_CACHE => [ HASH => \%cache ];

##</code><code>##

  
if(exists($args{HASH}))
  {
      $args{C} = $args{HASH};
  }
  else
  {
      $args{C} = \%cache;
  }