$address{$person};

##</code><code>##

if (not $is_seen{$case}++) { # etc

##</code><code>##

sub my_function {
  my %opts = @_;
  # etc

##</code><code>##

my $name = $self->{name};

##</code><code>##

if (exists $handler{$case}) {
  $handler{$case}->(); # Handle the special case
}