public function __construct()
{
// define our name, and our description
$this->setName('define');
$this->setShortDescription('override a setting in your story');
// what are the short switches?
$this->addShortSwitch('D');
// what is the required argument?
$this->setRequiredArg('<key=value>', "the setting you want to set in your story");
$this->setArgValidator(new Type_MustBeKeyValuePair());
// this argument is repeatable
$this->setSwitchIsRepeatable();
// all done
}