package Foo;

sub new {
   my ($class, $id) = @_;
   my $self = { id => $id };
   return bless $self, $class;
}

sub method {
   my ($self) = @_;
   ...
   if (...something went wrong...) {
      warn("$self->{id} rotted into a pile of mush\n");
   }
   ...
}

##</code><code>##

use Foo;
my $one = Foo->new('one');
my $second = Foo->new('two');