I'm not sure if I'm fully understanding what you want, but you could do something like this for your pack function: 
  sub pack {
        my $self=shift;
        my $record=join(':', @{$self}{keys %{$self->{_permitted}}});
        return $record;
  }

[download]
The keys of the _permitted element in your object are being used to index into the $self hash to extract the values. The problem with this is that you don't know what order the keys are going to come out. To solve that, I would suggest doing the initialization thusly: 
my @permitted=qw(name price description);
my %fields;
@fields{@permitted}=undef;

[download]
And then assign %fields to _permitted as before. But now you have also the @permitted array, which would allow you to write pack as follows, giving you control over the order in which the elements are packed: 
  sub pack {
        my $self=shift;
        my $record=join(':', @{$self}{@permitted});
        return $record;
  }

[download]

--ZZamboni

In reply to Re: Stumped on an OO Problem by ZZamboni
in thread Stumped on an OO Problem by skazat

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