I think I understand why this doesn't work but I'm having trouble coming up with a way around it.

I'm working on a bot that can talk on a variety of protocols. I want to be able to load the appropriate protocol when the bot starts and keep the code for each protocol in its own separate package. To do this I used the following code:

sub init {
    my $pkg = shift;
    my $proto = shift || $config->protocol();
    no strict 'refs'; 
    eval "require Bot::Protocol::$proto";
    if($@) {
        croak "Failed to load $proto.\n";
    }
}

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So far, so good. This works as long as my Bot::Protocol::$proto simply executes. However, I'd like to pass parameters to my protocols so that I don't have to include the config again etc. I tried using Exporter within the file I was requiring and then calling the sub. I tried a test case to eliminate the irrelavent parts

# in the main
my $pkg = shift;
no strict 'refs';  
eval "require $pkg";
if($@) {
    croak "Failed to load $pkg: $@\n";
}
print foobar();

[download]

And with the test I wrote two small packages, 'Foo' and 'Bar':

# in Foo.pm
package Foo;

use strict;
use Exporter;
use vars qw(@ISA @EXPORT);

@ISA = qw(Exporter);
@EXPORT = qw(foobar);

sub foobar {
    return "Foo!"; 
}
1;

[download]

(Bar.pm looks the same except it returns "Bar")

However of course I get "Undefined subroutine &main::foobar(). Now if I call it directly after I've required it with the eval, i.e. Foo::foobar() it works but to do that in my project I would have to use eval again as in eval "$pkg::foobar()", which seems a bit redundant. There must be a way to export it to everyone. Thanks in advance!

Lobster Aliens Are attacking the world!

In reply to Exporting subs from package required in an eval by cfreak

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