Dear Monks, having coded a lot in C++ in the last few months I'm now a bit paranoid and probably to C++-ish in my thinking. Therefore I'd be more than happy to be enlightened on the following problem by a real Perl guru :-)

I've created a class (let's call it CLASS) that has a nested data structure like this: 

my $self = {
         nest => [
                    [
                     [
                      1,
                      2,
                      3
                     ],
                     [
                      4,
                      5,
                      6
                     ],
                    ],
                 ],
         more => [
                  3,
                  2,
                  1
                 ]
};

[download]
Then I want to copy it like this: 
my $c1 = new CLASS;
my $c2 = $c1;

[download]
And next to that I need to change a value in the arrays of $c2. Since I have the instance variables as lots of references changing a value in $c2 always changes the corresponding value in $c1.

I had hoped that Perl would clean that mess for me but I doesn't seem so.

Now, do I need to write some sort of copy constructur (*yuck* even the word makes me shudder) and if so how do I do this or is there any other way of nicely solving this mess in a Perl-ish manner?

Thanks in advance for any pointers what to read or hints or code or other forms of enlightenment.

Regards... Stefan
you begin bashing the string with a +42 regexp of confusion

In reply to Deep Copying of Nested Data-Structures by stefan k

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