Does anyone know of a way to safely serialize (i.e. freeze/thaw) a data structure that has weak references? Here's an example: 
use strict;
use Storable qw(freeze thaw);
use Scalar::Util qw(weaken isweak);

# make a circular reference, then weaken it
my $a={};
$a->{a}=\$a;
weaken($a->{a});

# looks like we're ok
isweak($a->{a}) || die;

# serilize it
my $b=freeze($a);

# and unpack it
my $c=thaw($b);

# check if the weak reference survived the freeze
isweak($c->{a}) || die "nope!";

[download]
And it dies with "nope!". So far I've found one package on CPAN, "OOPS", that has planned support for serialzing weak references, but nothing currently exists... or maybe something does?

In reply to serializable weak references by Anonymous Monk

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