#!/usr/bin/perl
#
# SSCCE that demonstrates a problem encountered with
# Memoize 1.03 in old Perl. Tested successfully on Perl
# 5.20.3 to 5.28.0 where a ~2.6M cache is created.
# When run under Perl 5.18 on Mac OSX the cache grows
# to gigabytes and the program never seems to exit.
# Unsure if the problem is Perl, the module or OSX.

use strict;
use warnings;
use Carp;
use DB_File;
use Memoize;
use POSIX ();

my $cache = 1;
my @subs  = qw(two ten);

for my $sub (@subs) {
  my $file = $] . '_memoized_' . $sub;

  if ($cache) {
    no strict 'refs';
    if (my $db = tie %{$sub} => 'DB_File', $file, POSIX::O_RDWR|POSIX:
+:O_CREAT, 0666) {
      memoize $sub, SCALAR_CACHE => [HASH =>  \%{$sub}];
    }
    else {
      croak 'memo fail'
    }
  }
}

for my $n ('1' .. '100000') {
  $n = two($n);
  $n = ten($n);
  print "\r$n\t"
}

sub two {
  my $n = shift;
  $n = $n * 2;
  return $n
}

sub ten {
  my $n = shift;
  $n = $n * 10;
  return $n
}
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