Hello.

"clicked" may be a constant. It maybe imported when you declare to use some module.

#!/usr/bin/perl
use warnings;
use strict;

package notify;
use constant {
    active => 2,
};
1;

package main;
use constant {
    clicked=>1,
};

print clicked . "\n";
print notify::active . "\n";

exit;
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So, currently, you don't have package "notify" declaring "active" is a constant. If I am looking different direction, forgive me please.