Noname1.pm:

package Noname1;

use strict;
use Warnings;

my @added;

BEGIN {
    my %Seen = %INC;
    require CGI;
    @added = grep {! exists $Seen{$_}} keys %INC;
    }

sub Added {
    return @added;
}

1;
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Noname.pl:

use strict;
use Warnings;
use Noname1;
use CGI;

my @added = Noname1::Added ();

print "@added";
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Prints:

CGI/Util.pm CGI.pm
[download]