The proper word is recursive, not iterative. Iterative means something else.

The error occurs because the my hasn't occured at the time where $anon is used. (Assignments are processed right to left.) Therefore, the sub uses the package variable $main::anon. Cause the my to occur first by seperating the my from the assignment: 

my $anon;
$anon = sub {
   my $count = shift;
   if ($count--) {
        print "Iterating\n";
        $anon->($count);
   }
};

$anon->(4);

[download]

Update: Elaborated on the problem.

In reply to Re: Iterative anonymous subroutines by ikegami
in thread Iterative anonymous subroutines by Anonymous Monk

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