# warning, pseudocode
foo(4); # prints "4"
foo();  # prints "4"

sub foo {
  static int bar;
  bar = shift() unless defined bar;
  print bar;
}

##</code><code>##

sub too_slow {
  my $object = ReallyHuge::SlowObject -> new(%args);
  # do stuff with $object
  return "stuff";
}

##</code><code>##

sub less_slow {
  my $object;
  $object = $dbh -> @{selectall_arrayref("select object from storage")}[0];
  if ($object -> exists()) {
    # behave normally
  }
  else {
    $object = ReallyHuge::SlowObject -> new(%args);
    $dbh -> do("update storage set object='$object'");
  }
}