# MyTools.pm

package MyTools;

use warnings;
use strict;

sub import {

    my ($importing_package,
        $string_for_export,
        ) = @_;

    $string_for_export = '[default]' if ! defined $string_for_export;

    { no strict 'refs';  # turn off in narrowest scope
        # use a symbolic reference (gasp)
        ${ $importing_package . '::var' } = $string_for_export;
        }

    }

1;

##</code><code>##

# MyChest.pm

package MyChest;

use warnings;
use strict;

use parent qw(MyTools);

1;

##</code><code>##

# MyBag.pm

package MyBag;

use warnings;
use strict;

use parent qw(MyTools);

1;

##</code><code>##

# MyBox.pm

package MyBox;

use warnings;
use strict;

use parent qw(MyTools);

1;

##</code><code>##

use warnings;
use strict;

use MyChest 'Swiss Army knife';
use MyBox   '6-bladed screwdriver';
use MyBag;  # no string specified

print 'all variables printed from ', __PACKAGE__, ": \n";
print "    var in MyChest: '$MyChest::var' \n";
print "    var in MyBox: '$MyBox::var' \n";
print "    var in MyBag: '$MyBag::var' \n";

##</code><code>##

c:\@Work\Perl\monks\TerryBerry>perl set_in_importing_script_2.pl
all variables printed from main:
    var in MyChest: 'Swiss Army knife'
    var in MyBox: '6-bladed screwdriver'
    var in MyBag: '[default]'