Learned monks, I am writing a very abstract and challenging object-oriented application in Perl and I've hit the same problem a few times. It deals with the copying of objects...

I find in a number of classes, it is necessary to add a copy function like this (in the object package)... 


sub copy {
  my ($old)=@_;
  my $new_step=pathstep->new();
  foreach my $key (keys %{$old}) {
    # copy all attributes and values
    $new_step->{$key}=$old->{$key};
  }
  return $new_step;
}

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This is obviously a bit awkward and non-intuitive. What I would really like to do is this, at the application level: 
$copy=$original;  # DOES NOT WORK

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...except all that does is copy the reference, not the underlying data structure. Changes to $copy show up in $original. Another try on the problem is: 
%copy=%original;  # DOES NOT WORK

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...this complains in %copy being an unblessed reference. If you bless %copy in other than the proper module, it thinks it is the wrong kind of object (which can cause strange problems if the access functions are similar!).

It isn't a show stopper or anything - I essentially have it working - it just seems like there should be better way for future endeavors. It gets a bit more complicated when the copy operation is multi-layer (deep copies of objects within objects). The extra code just seems like an invitation to error.

Thanks in advance for your meditations.

(Hmmm, if I could overload operators, I would be in heaven!)

In reply to Copying Objects by lapointd

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