//! Futures type enumeration.
//!
//! Port of `ql/instruments/futures.hpp` (`struct Futures { enum Type }`). The
//! convention selects the date rule a futures contract settles on, and is read
//! only when building or validating a [`FuturesRateHelper`]'s schedule.
//!
//! [`FuturesRateHelper`]: crate::termstructures::yields::ratehelpers::FuturesRateHelper
/// The date convention a futures contract follows (`Futures::Type`).