Issues executing with ActivePerl 5.20

Question

I have a program which uses a module, located at the same folder that the executable but when I execute it it only closes.

use strict;
use warnings;
use genLetras;




for my $k (1 .. 30 ) {
        for my $j (1 .. 30 ) {
        genLetras::generarLetra();
        $matriz[$k][$j] = genLetras::generarLetra();
   }
}

for my $i (1 .. 30 ) {
        for my $j (1 .. 30 ) {
                     print "[$matriz[$k][$j]] ";
}
print "\n";
}

<>;

That is the code of the executable.

An this one is the modules's one

use strict;
use warnings;
use Math::Complex;

my $seed = time();
my $a = $seed / 5;
my $c = $seed - 7;
my $x = $seed;
my $m = sqrt($seed % 574) + $seed;
my $numAleatorio;


sub generadorMultiplicativo{
$numAleatorio = ((($a*$x) + $c) % $m);
$x = $numAleatorio;
}
my $letra;
my $residuo;
sub generarLetra{
   for my $i(1..30){
   generadorMultiplicativo();
    $residuo = $x/$m;

if($residuo < 0.0384615384615385 ){
       $letra = 'A';
} 
if($residuo > 0.0384615384615385 && $residuo < 0.076923076923077){
       $letra = 'B';
} 
if($residuo > 0.076923076923077 && $residuo < 0.1153846153846154){
       $letra = 'C';
}
if($residuo > 0.1153846153846154 && $residuo < 0.1538461538461538){
       $letra = 'D';
}
if($residuo > 0.1538461538461538 && $residuo < 0.1923076923076923){
       $letra = 'E';
}
if($residuo > 0.1923076923076923 && $residuo < 0.2307692307692308){
       $letra = 'F';
}
if($residuo > 0.2307692307692308 && $residuo < 0.2692307692307692){
       $letra = 'G';
}
if($residuo > 0.2692307692307692 && $residuo < 0.3076923076923077 ){
       $letra = 'H';
}
if($residuo > 0.3076923076923077 && $residuo < 0.3461538461538462){
       $letra = 'I';
}
if($residuo > 0.3461538461538462 && $residuo < 0.3846153846153846){
       $letra = 'J';
}
if($residuo > 0.3846153846153846 && $residuo < 0.4230769230769231){
       $letra = 'K';
}
if($residuo > 0.4230769230769231 && $residuo < 0.4615384615384615){
       $letra = 'L';
}
if($residuo > 0.4615384615384615 && $residuo < 0.5){
       $letra = 'M';
}
if($residuo > 0.4615384615384615 && $residuo < 0.5384615384615385){
       $letra = 'N';
}
if($residuo > 0.5384615384615385 && $residuo < 0.5769230769230769){
       $letra = 'O';
}
if($residuo > 0.5769230769230769 && $residuo < 0.6153846153846154){
       $letra = 'P';
}
if($residuo > 0.6153846153846154 && $residuo < 0.6538461538461538){
       $letra = 'Q';
}
if($residuo > 0.6538461538461538 && $residuo < 0.6923076923076923){
       $letra = 'R';
}
if($residuo > 0.6923076923076923 && $residuo < 0.7307692307692308){
       $letra = 'S';
}
if($residuo > 0.7307692307692308 && $residuo < 0.7692307692307692){
       $letra = 'T';
}
if($residuo > 0.7692307692307692 && $residuo < 0.8076923076923077){
       $letra = 'U';
}
if($residuo > 0.8076923076923077 && $residuo < 0.8461538461538462){
       $letra = 'V';
}
if($residuo > 0.8461538461538462 && $residuo < 0.8846153846153846){
       $letra = 'W';
}
if($residuo > 0.8846153846153846 && $residuo < 0.9230769230769231){
       $letra = 'X';
}
if($residuo > 0.9230769230769231 && $residuo < 0.9615384615384615){
       $letra = 'Y';
}
if($residuo > 0.9615384615384615 && $residuo < 1){
       $letra = 'Z';
}
return;
 }
}

I've already compiled both with perl-c , perl -V and all said it was correct.

I'm using ActivePerl 5.20 on Windows 10

Answer 1

Four things to consider here:

1. The module's filename must be genLetras.pm.

2. The main script must find it. Do as @ikegami suggested in his answer and add

   use FindBin qw( $RealBin );
   use lib $RealBin;
   

   before the use genLetras; line.

3. The module must end with some true value else the loader will complain. Add the line

   1;
   

   as the very last line to your module.

4. The module needs a line package genLetras; as the first line. Add that.

Further notes:

• Module names – by convention – usually start with an uppercase letter, like GenLetras, because lowercase letters are reserved for pragmas (like e.g. warnings or strict).

• I use FindBin usually like this:

  use FindBin;
  use lib $FindBin::Bin;
  

  but that's more a matter of taste.

• The <>; at the end of your main script normally is useless. I think you used it to prevent your Perl window from closing immediately but wait for you to press ENTER instead. That's ok then.

• I wonder why perl -c script.pl didn't show any errors. At my PC it did.

Answer 2

During your testing, you probably set the Current Directory to be the directory in which the script resides. The module could be found because the module search paths (@INC) includes ..

When it fails, the Current Directory was probably set to some other directory. The module couldn't be found because @INC didn't contain the directory in which it resides.

Add the following to add the script's directory to @INC:

use FindBin qw( $RealBin );
use lib $RealBin;