It looks like in the first case, you end up storing a reference to a piece of an existing hash in $ref_1->{2}{testX}{1}, and in the second case you get the actual bits of hash rather than a reference to another place in which they exist.

Sounds like you want use Storable qw(dclone), which performs a "deep clone" of nested data structures: 

use Storable qw(dclone);
foreach my $b1 (keys %{$ref_1->{'1'}}) {
    if(exists $ref_1->{'2'}->{$b1}) {
        $ref_1->{'2'}->{$b1}->{'1'} = dclone $ref_1->{'1'}->{$b1};
    }
}
print Dumper $ref_1;

[download]

Side note: In Perl, pointer syntax (->) is optional after the first one; that is, $ref_1->{1}->{test1}->{1} is equivalent to $ref_1->{1}{test1}{1}.

In reply to Re: Hash reference Problem by gamache
in thread Hash reference Problem by elLunes

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