try use vars or our

use vars and my are simplest. Another option that might be better in some situations (or worse in others) is to use a lexical (my) variable, and have functions that get/set/return a reference to it.

------------
:Wq
Not an editor command: Wq

I would use Exporter and create accessors for the data rather than accessing the data directly.

package Foo;

use warnings;
use strict;
use base 'Exporter';

our @EXPORT_OK = qw(
   some_data
   some_more_data
   fribble
);

sub some_data { 'foo' }
sub some_more_data { 'bar' }

my %gnarfles = (
    this => 1,
    that => 'one'
);

sub fribble {
    my $key = shift;
    if (exists $gnarfles{$key}) {
        return $gnarfles{$key};
    }
    else {
        die "No such value ($key)";
    }
}    

1;
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And in your actual program:

use Foo qw'fribble some_data';

my $result = fribble($key);
[download]

By properly encapsulating your data in accessors, you make it much easier to extend and make it easier to validate. Also, by adding it to @EXPORT_OK instead of @EXPORT, you ensure that people only import the functions that they need and, more importantly, it is very easy to track down where the function came from.

package Private_Stuff;

use strict;
use CGI::Carp qw(cluck); ### for log_error subroutine
use Time::Local; ### for datetime_to_epoch_secs subroutine

use vars qw($VERSION
            @ISA
            @EXPORT
            @EXPORT_OK
            $db_name);
require Exporter;

@ISA = qw(Exporter AutoLoader);
# Items to export into callers namespace by default. Note: do not expo
+rt
# names by default without a very good reason. Use EXPORT_OK instead.
# Do not simply export all your public functions/methods/constants.
@EXPORT = qw();
@EXPORT_OK = qw();

$VERSION = '0.01';

$db_name = "Some_Database_Name";

1; ### end of module

------------------------------------

test.pl
-------
  use Private_Stuff;
  print "The database name is ", $Private_Stuff::db_name, "\n";
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   perldoc perlmodlib
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