package Subs;
our $Foo = 3;
sub foo { $Foo++; }
1;

##</code><code>##

use Subs;
Subs::foo();
print $Subs::Foo, "\n";

##</code><code>##

package Subs;
BEGIN {
  use Exporter;
  our @ISA = qw(Exporter);
  our @EXPORT = qw($Foo &foo);
}
our $Foo = 3;
sub foo { $Foo++ }
1;

##</code><code>##

use Subs;
foo();
print $Foo, "\n";