In Perl, how do I put multiple packages in a single .pm file?

Question

I'm pretty sure that I read somewhere that it's possible, but there are a few gotchas that you need to be aware of. Unfortunately, I can't find the tutorial or page that described what you need to do. I looked through the Perl tutorials, and didn't find the one that I remember reading. Could someone point me to a page or document that describes how to put multiple packages into a single .pm file?

Answer 1

This is how I normally do it:

use strict; use warnings; use 5.010;  {     package A;     sub new   { my $class = shift; bless \$class => $class }     sub hello { say 'hello from A' } }  {     package B;     use Data::Dumper;     sub new   { my $class = shift; bless { @_ } => $class }     sub hello { say 'Hello from B + ' . shift->dump       }     sub dump  { Dumper $_[0] } }  $_->hello for A->new, B->new( foo => 'bar' ); 

Answer 2

You simply start off the new package with another package statement:

package PackageOne;  # ...... code  package PackageTwo;  # .... more code 

Problems with this approach (archived on 2009)