if ()

  if () {
  }

  if () {
  }
  else {
  }

  if ($foo) {
  }
  else {
  }

##</code><code>##

  open my $file, ...

  open my $file, ...
  close $file;

  open my $file, ...
  while () {
  }
  close $file;

  open my $file, ...
  while (<$file>) {
    chomp;
  }
  close $file;

##</code><code>##

  my $db = DBI->connect(...);
  END {$db and $db->rollback and $db->disconnect}