Hi, I've got a small question about the best way to preserve class data across calls to a cgi. In particular, I would like to set class defaults for an attribute, and preserve these defaults after inheriting the methods. For example, If I have the following code: 
#!/usr/bin/perl 

package a;

my $bar = 'bar';

sub foo {
  my $self = shift;
  @_ ? $bar = shift: $bar;
}

package b;
use base 'a';

sub new {
  my $class = shift;
  my $self = bless {}, ref($class)||$class;
  $self->foo('cow');
  return $self;
}


package main;

my $object = do "persistB.obj";

print $object->foo();

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where persistB.obj is simply a pre-built instance of class B: 
$VAR1 = bless( {}, 'b' );

[download]
then the call to $object->foo() return 'bar', instead of the intended 'cow'.

Now, back in the real world I need this to work for a project involving multiple objects inheriting common functions. In the interest of ease, I would like to have a simply setup routine that each class definition uses to set defaults for various attributes, keeping most of the implementation in some parent class.

I originally thought of having a BEGIN code block call a subroutine in the child object, but that won't work as BEGIN doesn't get any arguments passed to it.

Any ideas?

TIA,
webby

In reply to Persistent Class data by webby

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