class MyStore::PayMethod {
    # A submethod is a method that isn't inherited.
    submethod new { die "Create a subclass, silly." }
    method    authorize($price) { ... }
    method    execute($price) { ... }
    method    store($dbh) { ... }
}

class MyStore::PayMethod::CreditCard is MyStore::PayMethod {
    # Colon means private--only code in this class can see
    # it.
    has ($:ccnum, $:ccexp, $:ccname);
    submethod BUILD($:ccname, $:ccnum, $:ccexp) {}
    method    authorize($price) { (code to authorize) }
    method    execute($price) { (code to execute) }
    method    store($dbh) { (code to store) }
}