A follow up question might be: is there a way to have global variable shared between the main::space and the module::space so I don't have to keep passing the same values over and over? (I know, not a good idea, but just for the sake of discussion)

So, instead of:

#MAIN:
my $foo = "aaaaaaa";
my $bar = "bbbbbb";

print add_strings ($foo, $bar);
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Be able to just have:

#MAIN:
my $foo = "aaaaaaa";
my $bar = "bbbbbb";

print add_strings ();

#MODULE:
our ($foo, $bar); #this might be make-believe

add_strings {
   my $newstring = $foo . $bar;
   return ($newstring);
}
[download]