sub get_me_a_drink($drink_name) {
  if ($drink_name eq 'soda' or $drink_name eq 'beer') {
     # go to fridge
     # open fridge door
     # get drink
     return $drink
  }
  elsif ($drink_name eq 'coffee' or $drink_name eq 'tea') {
     # get water
     # boil water
     # mix ingredients
     return $drink
  }
  die "Can't make this drink";
}

##</code><code>##

sub get_me_a_drink($name) {
  if (is_cold($name)) {
     return get_from_fridge($name);
  }
  if (is_hot($name)) {
     return brew_hot_drink($name);
  }
  die "Can't make luke-warm drinks";
}

##</code><code>##

sub brew_hot_drink {
  my $ingredients = shift;
  my $water = get_water();
  my $hot = boil($water);
  my $drink = mix($hot,$ingredients);
  return $drink;
}

##</code><code>##

sub brew_hot_drink {
  my $ingredients = shift;
  return mix( $ingredients, boil(get_water()));
}