http://www.perlmonks.org?node_id=433594


in reply to Re: In need of a Dumper that has no pretentions to being anything else.
in thread In need of a Dumper that has no pretentions to being anything else.

My patch doesn't remove circular ref protection. Circular ref protection comes from keeping a track of all the refs we've seen so far and I've not touched that.

DD also keeps track of all scalars that it sees so that when you run this

use Data::Dumper; my %s=('key',1); my $s=\$s{'key'}; print Dumper([\%s, $s])
you get
$VAR1 = [ { 'key' => 1 }, \$VAR1->[0]{'key'} ];
that is, it was able to spot that the 1 in %s{key} is actually the same 1 that's in $s.

My patch removes this ability when $Deepcopy = 0. This is consistent with the rest of the deepcopy behaviour and means that now that the only thing that can cause a backreference to some other part of the structure is circularity.