in reply to sub-package question

use Foo::Bar @stuff; means exactly the following: 
BEGIN {
    require 'Foo/Bar.pm';
    Foo::Bar->import( @stuff );
}

[download]
where @stuff is if you do something like use Foo::Bar baz => 1;

Nowhere in Perl are the packages Foo and Foo::Bar related, except by convention.

------
We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested

In Section Seekers of Perl Wisdom