If you brace your packages, a la:

{
   package Foo::Bar;
   use strict;
   ...;
}

package Foo::Bar; {
   use strict;
   ...;
}

# Perl 5.14+
package Foo::Bar {
   use strict;
   ...;
}
[download]

... then it makes a difference, because lexically scoped pragma such as strict will end with the closing brace.

If you put multiple packages in the same file, then there are good arguments in favour of bracing each package - to prevent, e.g. leakage of our variables.