The Namespaces for your classes have not been declared, at the time you are attempting to use them.

Two possible fixes:
1. Move the "my $obj" line to the end ; or
2. add an INIT before each block declaring the class like this: 

INIT{ package TestClass;
...

[download]
You should also add a "1;" at the end of each class (Although your code works without that).

Update: Updated code. I find using "use base" more readable and safer than messing with @ISA; 

#!/usr/bin/perl
use strict;
use warnings;

my $obj=TestSubClass->new;

INIT{ package TestClass;
  sub new {
    my $class = shift;
    my $self = {};
    print "I'm brand new!\n";
    bless $self, $class;
  }
  1;
}

INIT{ package TestSubClass;
  use base "TestClass";
  1;
}

[download]

     Potentia vobiscum ! (Si hoc legere scis nimium eruditionis habes)

In reply to Re: basic inheritance question by NetWallah
in thread basic inheritance question by jason_s

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