#!/usr/bin/perl

use warnings;
use strict;

package Foo;

sub new {
    return bless {},shift;
}

sub hello {
    print "hello";
}

package main;

sub new {
    print "haha";
    return;
}

sub hello {
    print "Hi, $_[0]!";
}

my $a = new Foo;

hello $a;

__END__
Hi, Foo=HASH(0x814bd48)!