package Foo;
  use Plugin 'Bar';
  sub shared { print "Shared method" }
  sub foozle { print "Foo's foozle" }

  package Bar;
  our @PLUGIN_SUBS = qw(foozle);
  sub foozle { print "Bar's foozle" }

  # omitting Blip..
  #package Blip;
  #sub foozle { print "Blip's foozle" }

  #=======================
  
  package main;

  $package = 'Foo';
  $package->shared();
  $package->foozle();      # Calls ***Bar's*** foozle