question 1: simply, yes.

question 2: for what you are trying to do, exists is not the way to go. Also, you are using plugin:: as the name of the package, but for this to work, you would have to declare, package plugin; in all of your plugin files. Unloading, too, is more complicated than simply undef &plugin::do_stuff;.

You probably want each plugin to be a perl object, with all such objects derived from a common base class, rather like this:

# in Plugin.pm:
package Plugin;  # the common base class

sub new {
  my $type = shift;
  my $class = ref($type) || $type;

  return bless {}, $class;
}

# the public entry point, calls a private entry point in each derived 
+class, _do_stuff(), to actually do the work
sub do_stuff {
  my $self = shift;

  die 'Illegal plugin function' unless ($self->can('_do_stuff'));

  # polymorphic method call
  return $self->_do_stuff();
}

# in Whatever.pm:
package Whatever;

use base qw( Plugin );  # subclass of Plugin

sub new {
  my $type = shift;
  my $class = ref($type) || $type;

  return bless $class->SUPER::new, $class;
}

sub _do_stuff {
  # whatever this plugin does goes here
}

# etc.
[download]

Then, in your main program, you would have code similar to this:

use Basename;

for my $plugin_file ( ... ) {
  my $plugin_pkg = basename $pluginfile, '.pm';
  eval {
    use $plugin_pkg;
    my $plugin_object = new $plugin_pkg;
    $plugin_object->do_stuff();
  }
  if ($@) {
    # handle the error
  }
}
[download]

This way there'd be no name clashes nor would you necessarily have to unload a plugin, once loaded.

dmm

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