package Foo;
use MY;

sub new { bless {}, shift };

sub hello {
    my $self = shift;
    $self->MY::greet_world("hi");
};

sub MY::greet_world {
    my ($self, $greeting) = @_;
    print "$greeting world\n";
};


package Bar;
use base qw(Foo);
use MY;

sub new {
    my $class = shift;
    $class->MY::greet_world();
    return $class->SUPER::new(@_);
};

sub MY::greet_world {
    print "A new Bar has entered the world\n";
};