#include <optional>
#include <variant>

#include <QTypeInfo>

struct S {};
static_assert(!QTypeTraits::has_operator_less_than_v<S>);

using T = std::variant<S>;
static_assert(!QTypeTraits::has_operator_less_than_v<T>);

using U = std::optional<S>;
static_assert(!QTypeTraits::has_operator_less_than_v<U>);

// However
using V = std::optional<T>;
static_assert(QTypeTraits::has_operator_less_than_v<V>);