template<typename G, typename M>
struct DoMove {
private:
    constexpr static bool _isRLMove = (M::direction == Direction::LEFT
                                    || M::direction == Direction::RIGHT);
public:
    using result = typename Conditional<
            _isRLMove, DoMoveRL<G, M>, DoMoveUD<G, M>>::value::result;
};

template<bool C, template<typename ...> class...>
struct Conditional {
};


template<template<typename...> class C1, template<typename...> class C2>
struct Conditional<true, C1, C2> {
    template<typename... Ts>
    using apply = typename C1<Ts...>;
};


template<template<typename...> class C1, template<typename...> class C2>
struct Conditional<false, C1, C2> {
    template<typename... Ts>
    using apply = typename C1<Ts...>;
};

using result = typename Conditional<_isRLMove, DoMoveRL, DoMoveUD>::template apply<G, M>::result;

template<typename T> struct type { using type = T; };

auto choose_type() {
    if constexpr (_isRLMove) {
        return type<typename DoMoveRL<G, M>::result>{};
    } else {
        return type<typename DoMoveUD<G, M>::result>{};
    }
}

using result = decltype(choose_type())::type;