You can use weak references and get around this problem: 
use Scalar::Util 'weaken';
# ...
$self->{next} = (\$self == \$next) ? weaken(\$self) : \$next;

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Q on $var = \$var; by japhy
in thread Q on $var = \$var; by Bastiaan

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