I'd say that you were looking at the problem from the wrong end. In order that any code within your Blah module is run, you have to call it from the main program (unless it has a BEGIN{} INIT{} END{} etc. blocks, but thats a special case.).

So the way to tackle your problem is to pass the vars that you need to access in main into the code in Blah when you call it. Eg.

use Blah;
sub new{...}
sub doSomething{ 
    my $foobar = shift;
    $foobar->someMethod(); 
    ...
}
...
[download]

main

use Blah;
use FooBar;

my $f = FooBar->new();
my $b = Blah->new();

$b->doSomthing( $f );
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