package Foo;

our $var = "Hello";
sub func { print $var, "\n" }

package Bar;

print $var, "\n";  # Prints "Hello"
func();            # Error: Undefined subroutine &Bar::func called

##</code><code>##

{
    package Foo;
    our $var = "Hello";
    sub func { print $var, "\n" }
}
{
    package Bar;
    print $Foo::var, "\n";
    Foo::func();
}
# Or, as of Perl 5.14:
package Foo {
    ...
}
package Bar {
    ...
}

##</code><code>##

package Foo {
    our $var = "Hello";
    sub func { print $var, "\n" }
}
package Bar {
    use Symbol::Alias '$Foo::var' => 'var', 'Foo::func' => 'func';
    print $var, "\n";
    func();
}