...
package Foo;
...
package Bar;
...

##</code><code>##

{
   my $foo;
   {
      my $bar;
      ...
   }
   ...
}

##</code><code>##

for (1..2) {
   my $x;        # New variable each time.
   print($x);
}

##</code><code>##

package Foo;
use Carp qw( carp );
carp('One');

package Bar;
...

package Foo;
carp('Two');

##</code><code>##

package Foo;
use Carp qw( carp );
carp('One');

package Bar;
Foo::carp('Two');

package Foo;
carp('Three');