require Abc;
Abc->import();

simple();
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hm... still doesn't seem to be solution: Undefined subroutine &main::generate_throws_simple called at (...) and the code:

use strict;
use warnings;

use vars qw($a $b @wyniki);
$a = 6;   #kostka 
$b = 10;  #licznik
@wyniki = ();

require gts; #generate_throws_simple
require pts; #print_throws_simple

gts->import();
pts->import();

print "\n-------------------STANDARDOWE LOSOWANIE----------------\n";
print_throws_simple(generate_throws_simple($a,$b)); #standardowe losow
+anie
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and gts/pts code (just that important):

require Exporter;
our @ISA = qw(Exporter);
our @EXPORT = qw(print_throws_simple); # symbols automatically exporte
+d
our @EXPORT_OK = qw(); # symbols exported on request
our %EXPORT_TAGS = (); # TAG => [qw(name1 name2)]
# ...............................................
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Well, the exporting needs to happen at use(BEGIN) time , so if you don't want to use use, you have to wrap require/importing in  BEGIN {} , or delay compilation of  print_throws_simple(generate_throws_simple($a,$b)); with  eval q{ }

I suggest you do whatever it takes to be able to use use