#### test.pl
#!/usr/bin/perl -w

use strict;
use plugins;

my $P = new plugins();
$P->loadplugins();

sub registerplugin {
  $P->registerplugin(@_);
}
#### end

#### plugins.pm
package plugins;

use wrap;

sub new {
  my $class = shift;
  my $self = {};
  bless($self, $class);
  return $self;
}

sub loadplugins {
  my $self=shift;
  wrap::requirer('foo.pl');
}

sub registerplugin {
  my $self = shift;
  my $arg = shift;
  print $arg;
}
1;
#### end

#### wrap.pm
package wrap;

sub requirer {
  require 'foo.pl';
}

sub registerplugin {
  main::registerplugin(@_);
}
1;
#### end

#### foo.pl
registerplugin("hi");
#### end