Re: Inheritance in Perl5

Perl tends to like its packages defined before they're used. Try putting both your packages inside a BEGIN block. ie

my $horse1 = Horse->new("George the Horse", 12);
$horse1->present();
$horse1->animalmethod();

BEGIN {
    package Animal;

    ...

    package Horse;

    ...
}
[download]

Update:

I forgot I was going to point you towards Moose. It's a nicer way of writing OO Perl. Then, try MooseX::Declare for a much nicer way.

Comment on Re: Inheritance in Perl5 Download Code

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Re^2: Inheritance in Perl5 by chromatic (Archbishop) on Aug 08, 2009 at 18:17 UTC
Perl tends to like its packages defined before they're used. Indeed, this is why the Perl 5 parser creates namespaces and installs subroutines into those name spaces at compilation time. Except for code which creates an object in a `BEGIN` block before the parser has even read the class `package` declaration, this order does not matter. The OP's question is similar to: `ok( foo(), 10, 'foo() should return value of $bar' ); my $bar = 10; sub foo { return $bar }` [download]	[reply] [d/l] [select]
Re^2: Inheritance in Perl5 by EvanCarroll (Chaplain) on Aug 08, 2009 at 17:46 UTC
The moose way you speak of: `package Animal; use Moose; has [qw/name age/] => ( isa => 'Str', is => 'rw' ); package Horse; use Moose; extends 'Animal'; sub present { my $self = shift; print $self->isa('Animal') ? "I am an animal" : "I am not animal" }` [download] With that said, I think there is something seriously wrong if you want your subclass to confirm that it inherits from the parent class in a method ;) Evan Carroll The most respected person in the whole perl community. www.EvanCarroll.com	[reply] [d/l]