in reply to Share Variable in Script with a Module

As boftx points out your problem is that my_sub() is called before the import() so your variable is not initialised - if you use warnings it will tell you this. Also, the first argument to import is the class name, so you should shift that first: 
package my_module;

$VERSION = '1.00';

use strict;
use warnings;
our $gMessage;

sub import {
    my $class = shift;
    $gMessage = shift;
    print "Yep, I'm in here ...\n\n";
    my_sub();
}

sub my_sub {
    print $gMessage;
}
1;

[download]
Output: 
Yep, I'm in here ...

xyz

[download]

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Re^2: Share Variable in Script with a Module
by DanielSpaniel (Scribe) on Oct 05, 2013 at 00:57 UTC
    Okay, thank you both. I'll have another try at it tomorrow.
[reply]
Re^2: Share Variable in Script with a Module
by DanielSpaniel (Scribe) on Oct 09, 2013 at 16:44 UTC

    Okay, that does work, but seems to introduce another problem, which I don't quite understand.

    The test module, and test script, are shown below:

    The module 
    package my_testmodule;

$VERSION = '1.00';

use strict;
use warnings;
our $gMessage;

undef our @list;

use Exporter;
our @ISA    = qw(Exporter);
our @EXPORT = qw(@list);

sub import {
    my $class = shift;
    $gMessage = shift;
    print "Yep, I'm in here ...\n\n";
    my_sub();
}

# &my_sub;

sub my_sub {
    print "$gMessage\n\n" if ($gMessage);

    push (@list,'oranges','lemons','apples');
}
1;

    [download]
    The script 
    #!/usr/bin/perl

use strict;
use warnings;

use my_testmodule 'xyz';

print "$list[0]\n\n";

exit;

    [download]

    Previously, before trying to pass the module anything at all, and thus without the import sub, I would be able to read @list, defined in the module, in test.pl.

    However, now, with the import sub, I'll get an error when running test.pl, "Global symbol "@list" requires explicit package name at test.pl line 8."

    I don't see why this should be, seeing as it appears to be defined and exported properly in the module; in fact nothing to do with @list has changed.

    I did also try referencing @list with the package name, but that doesn't work either.

    Any help/suggestions would be much appreciated. Thanks!

[reply]
[d/l]
[select]
      By defining an import method in your module you are overriding Exporter's own import method so it never gets called and doesn't export your list. To fix that, add the following line: 
      sub import {
    my_testmodule->export_to_level(1, @_);
    my $class = shift;
    $gMessage = shift;
    print "Yep, I'm in here ...\n\n";
    my_sub();
}

      [download]
      See the Exporter module's documentation for more.
[reply]
[d/l]

        Thank you very much.

        In fact, I did re-post as a new question, because I figured that this original thread was too far down the list to get any attention, but I received the same answer on each, and it works great now.

        Thank you again.
[reply]

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