This must be very common/standard OO machinery, but it seems that only at an extremely slow pace can I grasp object oriented concepts and techniques.

I would like to have a class, say MyClass each instance object of which holds some data, and having a method, say item really returning an object of another class, e.g. MyClass::Item. Now I want the latter to have access both to its specific data and to the instance data of the MyClass object.

I was thinking of a naive solution based on simply passing info about MyClass's specific instance to MyClass::Item 's constructor, a' la:

(example trimmed down to a bare minimum.) 

#!/usr/bin/perl -l

use strict;
use warnings;


package MyClass;

sub new {
    my ($class, $data)=@_;
    bless { DATA => $data }, $class;
}

sub item {
    my $self=shift;
    MyClass::Item->new($self,@_);
}


package MyClass::Item;

sub new {
    my ($class, $daddy, $data)=@_;
    bless { DADDY => $daddy,
            DATA => $data }, $class;
}    

sub info {
    my $self=shift;
    "Generic data: ", $self->{DADDY}{DATA}, 
      " - ",
      "This item's data: ", $self->{DATA};
}


package main;

my $c=MyClass->new('Foo');
my @items=map $c->item($_), qw/aa bb cc/;
print $_->info for @items;

__END__

[download]

However I strongly suspect that there may be better ways...

In reply to Instance data inheritance? by blazar

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