I have written a program.. 
test.pl
------
#!/usr/bin/perl -w

use strict;
use test_module;

my $var=10;
my $new_var=testsub($var);
print "$new_var\n";

[download]
..and my first module.. 

test_module.pm
-----------------------
sub testsub
{
    my $in_arg=@_;
    my $new_arg=$in_arg+10;
    return($new_arg);
}

1;

[download]
Could someone explain why this construct prints out "11" instead of 20?? Thank you for your help.

In reply to My first module by tamaguchi

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