In the aXML doc
---------------

  <foo bar="hello" baz="world">
     good to be here
  </foo>

  

In your sites private subs module
---------------------------------

my $plugins = {

   foo => sub { 
               my $args = $_[0];  #a hashref
               my $data = $_[1];  #good to be here

               $args->{'tag_name'};  #foo  
               $args->{'bar'};       #hello
               $args->{'baz'};       #world 

               #do some stuff with the args and data here
 
               return 'some result'; 
             }
       };


##</code><code>##

 
  lt => sub { return '<'; }

or 

  lt => sub { '<' }   #golfed :P