package Foo;
use strict;
use warnings;

my $_init_ = sub {
  my $self = shift;
  print STDERR ref($self) . "::_init_ called\n";
};

sub new {
  my $type = shift;
  my $class = ref($type) || $type;
  my $self = {
    attribute1 => undef,
    attribute2 => undef,
  };
  bless $self,$class;
  $self->$_init_();
  return $self;
}

1;