use base 'Exporter'
our @EXPORT = qw(compress);
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2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$
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I can't get that to work in my script. ;[ If i "require" a module from my main script, that module can't reach "compress" by simply calling "compress", only by calling "GLOBAL->compress". This is my test setup:

main.pl

#!/usr/bin/perl -w

use GLOBAL;
compress "main\n";

require "MODULE.pm";
MODULE->test;
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GLOBAL.pm

package GLOBAL;

use base 'Exporter'
our @EXPORT = qw(compress);

sub compress {
  print shift;
}

1;
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MODULE.pm

package MODULE;

sub test {
  compress "test\n";
}

1;
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Did i just do something wrong is it impossible to use "compress" like this?

Just as a note, your module should look like (at least in 5005_03):

package GLOBAL
use 'Exporter';
@ISA = qw(Exporter); #not always needed, but usually a good practice
@EXPORT = qw(compress);
...

1;

package MODULE

use GLOBAL;
use Exporter;
@ISA = qw(Exporter); #again, usually a good practice.
@EXPORT = qw(test);

sub test {
compress "test\n";
}

1;
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I may be incorrect in the new perl 5.6+ world since I'm still using 5.005_03. The only reason I added the use statement to the MODULE package is to make sure that the sub compress is pushed into it.

Hope this helps, but YMMV.

Theodore Charles III
Network Administrator
Los Angeles Senior High
4650 W. Olympic Blvd.
Los Angeles, CA 90019
323-937-3210 ext. 224
email->secon_kun@hotmail.com

First, there is an error in GLOBAL.pm

package GLOBAL;

use base 'Exporter'
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is missing ';'
use base 'Exporter';

our @EXPORT = qw(compress);

sub compress {
  print shift;
}

1;
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Second, add use GLOBAL; to MODULE.pm

package MODULE;

use GLOBAL;

sub test {
  compress "test\n";
}

1;
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HTH,
Charles K. Clarkson

Exporting (through Exporter or otherwise) comes in two parts. The code to export needs to declare what it will export. That's what using Exporter and populating @EXPORT or @EXPORT_OK does for you.

The code that wants to import also must do something -- namely, asking the other code to import stuff. If you require MODULE, you need to call MODULE->import(). If you use MODULE, Perl will call import() automatically.

Where did import() come from in MODULE? It came from using Exporter. If you'd require()d Exporter, you'd have had to call Exporter->import().

Does that help?

It is not to my knowledge any way to let your Global.pm module "become a part of Perl", if that is what you want. Any piece of code that needs anything from your Global.pm will have to

use Global.pm
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I found it to be a rather steep learning curve to learn the Perl Module concept. Then I found it to be an even steeper learning curve to understand the Perl OO modules.

Nevertheless, I strongly recommend you to take the time necessary to learn the OO module programming. You will be rewarded for your efforts.

The white hole.

I think this was a 5.6+ feature. For what you go, I would write it as such:

sub compress ($) {
    my $val = shift;
    # Do stuff with $val
}
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sub compress (\@@) {
    my $array = shift;
    my @values = @_;

    # Do stuff with the listref $array and the list of scalars @values
}
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------
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Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.