use strict;
use warnings;
use Data::Dumper;

my $foo = { foo => [qw{d e f}], bar => [qw{g h i}]};
my %bar = ( foo => [qw{m n o}], bar => [qw{p q r}]);
bless $foo, 'FooStuff';
bless \%bar, 'FooStuff';

sub FooStuff::myMethod (\%) {
        my $self = shift;
        print Dumper($self);
} 

$foo->myMethod;
FooStuff::myMethod(%bar);